Wanger Advisors Trust

Form N-CSR is to be used by management investment companies to file reports with the Commission not later than 10 days after the transmission to stockholders of any report that is required to be transmitted to stockholders under Rule 30e-1 under the Investment Company Act of 1940 (17 CFR 270.30e-1). The Commission may use the information provided on Form N-CSR in its regulatory, disclosure review, inspection, and policymaking roles.

A registrant is required to disclose the information specified by Form N-CSR, and the Commission will make this information public. A registrant is not required to respond to the collection of information contained in Form N-CSR unless the Form displays a currently valid Office of Management and Budget ("OMB") control number. Please direct comments concerning the accuracy of the information collection burden estimate and any suggestions for reducing the burden to Secretary, Securities and Exchange Commission, 100 F Street, NE, Washington, DC 20549. The OMB has reviewed this collection of information under the clearance requirements of 44 U.S.C. § 3507.

Table of Contents

Fund at a Glance	3
Understanding Your Fund’s Expenses	5
Portfolio of Investments	6
Statement of Assets and Liabilities	10
Statement of Operations	11
Statement of Changes in Net Assets	12
Financial Highlights	13
Notes to Financial Statements	14
Liquidity Risk Management Program	25
Board Consideration and Approval of Advisory Agreement	25

Proxy voting policies and procedures

The policy of the Board of Trustees is to vote the proxies of the companies in which Wanger International (the Fund) holds investments consistent with the procedures as stated in the Statement of Additional Information (SAI). You may obtain a copy of the SAI without charge by calling 800.345.6611; contacting your financial intermediary; visiting columbiathreadneedleus.com/investor/; or searching the website of the Securities and Exchange Commission (SEC) at sec.gov. Information regarding how the Fund voted proxies relating to portfolio securities is filed with the SEC by August 31st for the most recent 12-month period ending June 30th of that year, and is available without charge by visiting columbiathreadneedleus.com/investor/, or searching the website of the SEC at sec.gov.

Quarterly schedule of investments

The Fund files a complete schedule of portfolio holdings with the SEC for the first and third quarters of each fiscal year on Form N-PORT. The Fund’s Form N-PORT is available on the SEC’s website at sec.gov. The Fund’s complete schedule of portfolio holdings, as filed on Form N-PORT, is available on columbiathreadneedleus.com/investor/ or can also be obtained without charge, upon request, by calling 800.345.6611.

Additional Fund information

Fund investment manager

Columbia Wanger Asset Management, LLC (the Investment Manager)

71 S Wacker Drive, Suite 2500

Chicago, IL 60606

888.4.WANGER

(888.492.6437)

Fund distributor

Columbia Management Investment Distributors, Inc.

290 Congress Street

Boston, MA 02210

Fund transfer agent

Columbia Management Investment Services Corp.

P.O. Box 219104

Kansas City, MO 64121-9104

Wanger International | Semiannual Report 2022

Table of Contents

Fund at a Glance
(Unaudited)

Investment objective

The Fund seeks long-term capital appreciation.

Portfolio management

Tae Han (Simon) Kim, CFA

Co-Portfolio Manager since 2017

Service with Fund since 2011

James Chapman, CFA

Co-Portfolio Manager since 2020

Service with Fund since 2018

Zoe Tan, CFA

Co-Portfolio Manager since 2020

Service with Fund since 2018

Average annual total returns (%) (for the period ended June 30, 2022)
	Inception	6 Months cumulative	1 Year	5 Years	10 Years	Life of Fund
Wanger International	05/03/95	-35.36	-30.64	0.78	4.90	9.88
MSCI ACWI ex USA Small Cap Growth Index (Net)		-28.13	-27.34	2.97	6.31	-
MSCI ACWI ex USA Small Cap Index (Net)		-22.92	-22.45	2.55	6.22	-

Performance data shown represents past performance and is not a guarantee of future results. The investment return and principal value will fluctuate so that shares, when redeemed, may be worth more or less than the original cost. Current performance may be lower or higher than the performance data shown. Performance results reflect any fee waivers or reimbursements of Fund expenses by the Investment Manager and/or any of its affiliates. Absent these fee waivers and/or expense reimbursement arrangements, performance results would have been lower. For most recent month-end performance updates, please visit columbiathreadneedleus.com/investor/.

Performance numbers reflect all Fund expenses but do not include any fees and expenses imposed under your variable annuity contract or life insurance policy or qualified pension or retirement plan. If performance numbers included the effect of these additional charges, they would be lower.

The Fund’s annual operating expense ratio of 1.20% is stated as of the Fund’s prospectus dated May 1, 2022, and differences in expense ratios disclosed elsewhere in this report may result from the reflection of fee waivers and/or expense reimbursements as well as different time periods used in calculating the ratios.

All results shown assume reinvestment of distributions.

The MSCI ACWI ex USA Small Cap Growth Index (Net) captures small-cap securities exhibiting overall growth style characteristics across 22 of 23 developed markets countries (excluding the United States) and 24 emerging market countries.

The MSCI ACWI ex USA Small Cap Index (Net) captures small-cap representation across 22 of 23 developed market countries (excluding the United States) and 24 emerging market countries.

Indexes are not managed and do not incur fees or expenses. It is not possible to invest directly in an index.

Wanger International | Semiannual Report 2022

Table of Contents

Fund at a Glance (continued)
(Unaudited)

Equity sector breakdown (%) (at June 30, 2022)
Communication Services	6.9
Consumer Discretionary	7.8
Consumer Staples	3.5
Financials	6.9
Health Care	19.8
Industrials	26.5
Information Technology	20.6
Materials	4.4
Real Estate	3.6
Total	100.0

Percentages indicated are based upon total equity investments. The Fund’s portfolio composition is subject to change.

Country breakdown (%) (at June 30, 2022)
Australia	6.2
Brazil	1.9
Canada	2.3
China	1.4
Denmark	3.9
Finland	1.6
France	1.2
Germany	7.3
Hong Kong	0.5
India	1.0
Italy	5.2
Japan	16.9
Mexico	1.6
Netherlands	4.0
New Zealand	0.4
South Korea	2.4
Spain	0.5
Sweden	8.3
Switzerland	4.4
Taiwan	6.6
United Kingdom	17.9
United States^(a)	3.2
Vietnam	1.3
Total	100.0

(a)	Includes investments in Money Market Funds.

Country breakdown is based primarily on issuer’s place of organization/incorporation. Percentages indicated are based upon total investments, excluding investments in derivatives, if any. The Fund’s portfolio composition is subject to change.

4	Wanger International \| Semiannual Report 2022

Table of Contents

Understanding Your Fund’s Expenses
(Unaudited)

As a shareholder, you incur three types of costs. There are shareholder transaction costs, which may include redemption fees. There are also ongoing fund costs, which generally include investment advisory fees and other expenses for Wanger International (the Fund). Lastly, there may be additional fees or charges imposed by the insurance company that sponsors your variable annuity and/or variable life insurance product. The following information is intended to help you understand your ongoing costs (in dollars) of investing in the Fund and to help you compare these costs with the ongoing costs of investing in other mutual funds.

Analyzing your Fund’s expenses

To illustrate these ongoing costs, we have provided an example and calculated the expenses paid by investors in the Fund during the period. The actual and hypothetical information in the table below is based on an initial investment of $1,000 at the beginning of the period indicated and held for the entire period. Expense information is calculated two ways and each method provides you with different information. The amount listed in the “Actual” column is calculated using the Fund’s actual operating expenses and total return for the period. You may use the Actual information, together with the amount invested, to estimate the expenses that you paid over the period. Simply divide your account value by $1,000 (for example, an $8,600 account value divided by $1,000 = 8.6), then multiply the results by the expenses paid during the period under the Actual column. The amount listed in the “Hypothetical” column assumes a 5% annual rate of return before expenses (which is not the Fund’s actual return) and then applies the Fund’s actual expense ratio for the period to the hypothetical return. You should not use the hypothetical account values and expenses to estimate either your actual account balance at the end of the period or the expenses you paid during the period. See “Compare with other funds” below for details on how to use the hypothetical data.

Compare with other funds

Since all mutual funds are required to include the same hypothetical calculations about expenses in shareholder reports, you can use this information to compare the ongoing cost of investing in the Fund with other funds. To do so, compare the hypothetical example with the 5% hypothetical examples that appear in the shareholder reports of other funds. As you compare hypothetical examples of other funds, it is important to note that hypothetical examples are meant to highlight the ongoing cost of investing in a fund only and do not reflect any transaction costs, such as redemption or exchange fees. Therefore, the hypothetical calculations are useful in comparing ongoing costs only, and will not help you determine the relative total costs of owning different funds. If transaction costs were included in these calculations, your costs would be higher.

January 1, 2022 — June 30, 2022
	Account value at the beginning of the period ($)		Account value at the end of the period ($)		Expenses paid during the period ($)		Fund’s annualized expense ratio (%)
	Actual	Hypothetical	Actual	Hypothetical	Actual	Hypothetical	Actual
Wanger International	1,000.00	1,000.00	646.40	1,018.70	5.02	6.16	1.23

Expenses paid during the period are equal to the Fund’s annualized expense ratio, multiplied by the average account value over the period, then multiplied by the number of days in the Fund’s most recent fiscal half-year and divided by 365.

Had the Investment Manager and/or certain of its affiliates not waived/reimbursed certain fees and expenses, account value at the end of the period would have been reduced. See Note 3 to the Financial Statements.

It is important to note that the expense amounts shown in the table are meant to highlight only ongoing costs of investing in the Fund. Expenses paid during the period do not include any insurance charges imposed by your insurance company’s separate account. The hypothetical example provided is useful in comparing ongoing costs only and will not help you determine the relative total costs of owning different funds whose shareholders may incur transaction costs.

Wanger International | Semiannual Report 2022

Table of Contents

Portfolio of Investments
June 30, 2022 (Unaudited)

(Percentages represent value of investments compared to net assets)

Investments in securities

Common Stocks 97.9%
Issuer	Shares	Value ($)
Australia 6.1%
Bapcor Ltd.	1,234,467	5,188,223
carsales.com Ltd.	239,052	3,038,323
IDP Education Ltd.	318,201	5,210,583
Johns Lyng Group Ltd.	536,673	2,124,823
Pro Medicus Ltd.	121,668	3,555,583
Total		19,117,535
Brazil 1.9%
Hapvida Participacoes e Investimentos SA	1,602,924	1,672,313
TOTVS SA	928,425	4,135,243
Total		5,807,556
Canada 2.3%
Altus Group Ltd.	93,373	3,234,542
Osisko Gold Royalties Ltd.	389,806	3,930,766
Total		7,165,308
China 1.4%
Silergy Corp.	54,000	4,366,406
Denmark 3.8%
ALK-Abello A/S^(a)	386,686	6,736,458
Netcompany Group AS^(a)	29,691	1,635,728
SimCorp AS	48,711	3,560,905
Total		11,933,091
Finland 1.6%
Valmet OYJ	197,837	4,875,363
France 1.1%
Robertet SA	4,011	3,562,961
Germany 7.3%
Eckert & Ziegler Strahlen- und Medizintechnik AG	52,976	2,036,026
Hypoport SE^(a)	9,676	1,929,873
Jenoptik AG	140,595	3,162,459
Nemetschek SE	72,912	4,435,724
Secunet Security Networks AG	4,126	1,233,191
Washtec AG	211,612	9,883,137
Total		22,680,410
Hong Kong 0.5%
Modern Dental Group Ltd.	3,925,000	1,586,510

Common Stocks (continued)
Issuer	Shares	Value ($)
India 1.0%
Balkrishna Industries Ltd.	114,379	3,127,387
Italy 5.2%
Amplifon SpA	170,790	5,250,865
Carel Industries SpA	233,001	4,634,830
GVS SpA^(a)	242,116	1,979,508
Intercos SpA^(a)	327,751	4,319,901
Total		16,185,104
Japan 16.7%
Aruhi Corp.	598,700	4,477,295
Avant Corp.	1,146,900	11,371,754
CyberAgent, Inc.	317,700	3,182,891
Daiseki Co., Ltd.	278,480	8,693,297
Fuso Chemical Co., Ltd.	114,600	3,002,641
Hoshizaki Corp.	172,200	5,132,579
Seiren Co., Ltd.	122,800	1,831,272
Sekisui Chemical Co., Ltd.	244,800	3,356,205
Simplex Holdings, Inc.	262,900	3,388,478
Solasto Corp.	1,208,200	6,513,799
Valqua Ltd.	73,800	1,391,062
Total		52,341,273
Mexico 1.6%
Corporación Inmobiliaria Vesta SAB de CV	2,673,962	4,986,378
Netherlands 3.9%
Argenx SE, ADR^(a)	8,335	3,157,965
BE Semiconductor Industries NV	49,839	2,381,517
IMCD NV	49,633	6,786,545
Total		12,326,027
New Zealand 0.4%
Fisher & Paykel Healthcare Corp., Ltd.	103,095	1,284,326
South Korea 2.4%
Koh Young Technology, Inc.	237,818	2,597,609
Korea Investment Holdings Co., Ltd.	102,130	4,868,423
Total		7,466,032
Spain 0.5%
Vidrala SA	21,255	1,544,008

The accompanying Notes to Financial Statements are an integral part of this statement.

6	Wanger International \| Semiannual Report 2022

Table of Contents

Portfolio of Investments (continued)
June 30, 2022 (Unaudited)

Common Stocks (continued)
Issuer	Shares	Value ($)
Sweden 8.2%
AddTech AB, B Shares	465,076	6,085,743
Dometic Group AB	408,136	2,407,581
Dustin Group AB	463,188	2,651,738
Munters Group AB	762,523	4,444,974
Sectra AB, Class B^(a)	636,180	8,553,750
Sweco AB, Class B	140,549	1,464,852
Total		25,608,638
Switzerland 4.4%
Belimo Holding AG, Registered Shares	17,717	6,237,786
Inficon Holding AG	3,795	2,992,059
Kardex Energy AG	13,078	2,180,644
Montana Aerospace AG^(a),(b)	149,584	2,313,439
Total		13,723,928
Taiwan 6.6%
Parade Technologies Ltd.	169,000	6,579,282
Sinbon Electronics Co., Ltd.	531,000	4,549,011
Universal Vision Biotechnology Co., Ltd.	196,000	1,880,786
Voltronic Power Technology Corp.	155,495	7,543,142
Total		20,552,221
United Kingdom 17.7%
Abcam PLC^(a)	247,936	3,563,510
Auto Trader Group PLC	748,811	5,071,363
Dechra Pharmaceuticals PLC	246,164	10,379,581
Diploma PLC	266,762	7,265,154

Common Stocks (continued)
Issuer	Shares	Value ($)
Genus PLC	141,683	4,325,566
Intermediate Capital Group PLC	503,983	8,057,459
Porvair PLC	610,231	4,026,161
Rightmove PLC	1,416,425	9,815,594
Safestore Holdings PLC	216,098	2,798,149
Total		55,302,537
United States 2.0%
Inter Parfums, Inc.	87,725	6,409,189
Vietnam 1.3%
Asia Commercial Bank JSC^(a)	1,912,375	1,975,693
FPT Corp.	533,040	1,977,305
Total		3,952,998
Total Common Stocks (Cost $302,685,091)		305,905,186

Money Market Funds 1.2%
	Shares	Value ($)
Columbia Short-Term Cash Fund, 1.247%^(c),(d)	3,567,613	3,565,472
Total Money Market Funds (Cost $3,565,197)		3,565,472
Total Investments in Securities (Cost $306,250,288)		309,470,658
Other Assets & Liabilities, Net		2,953,589
Net Assets		$312,424,247

At June 30, 2022, securities and/or cash totaling $56,670 were pledged as collateral.

Investments in derivatives

Long futures contracts
Description	Number of contracts	Expiration date	Trading currency	Notional amount	Value/Unrealized appreciation ($)	Value/Unrealized depreciation ($)
MSCI Emerging Markets Index	34	09/2022	USD	1,704,590	—	(12,673)

Notes to Portfolio of Investments

(a)	Non-income producing investment.
(b)	Represents privately placed and other securities and instruments exempt from Securities and Exchange Commission registration (collectively, private placements), such as Section 4(a)(2) and Rule 144A eligible securities, which are often sold only to qualified institutional buyers. At June 30, 2022, the total value of these securities amounted to $2,313,439, which represents 0.74% of total net assets.
(c)	The rate shown is the seven-day current annualized yield at June 30, 2022.

The accompanying Notes to Financial Statements are an integral part of this statement.

Wanger International | Semiannual Report 2022

Table of Contents

Portfolio of Investments (continued)
June 30, 2022 (Unaudited)

Notes to Portfolio of Investments (continued)

(d)

As defined in the Investment Company Act of 1940, as amended, an affiliated company is one in which the Fund owns 5% or more of the company’s outstanding voting securities, or a company which is under common ownership or control with the Fund. The value of the holdings and transactions in these affiliated companies during the period ended June 30, 2022 are as follows:

Affiliated issuers	Beginning of period($)	Purchases($)	Sales($)	Net change in unrealized appreciation (depreciation)($)	End of period($)	Realized gain (loss)($)	Dividends($)	End of period shares
Columbia Short-Term Cash Fund, 1.247%
	3,341,553	47,119,770	(46,896,194)	343	3,565,472	(1,306)	13,007	3,567,613

Abbreviation Legend

ADR	American Depositary Receipt

Currency Legend

USD

US Dollar

Fair value measurements

Various inputs are used in determining the value of the Fund’s investments, following the input prioritization hierarchy established by accounting principles generally accepted in the United States of America (GAAP). These inputs are summarized in the three broad levels listed below:

■	Level 1 – quoted prices in active markets for identical securities

■	Level 2 – prices determined using other significant observable inputs (including quoted prices for similar securities, interest rates, prepayment speeds, credit risk and others)

■	Level 3 – prices determined using significant unobservable inputs where quoted prices or observable inputs are unavailable or less reliable (including management’s own assumptions about the factors market participants would use in pricing an investment)

The inputs or methodology used for valuing securities are not necessarily an indication of the risk associated with investing in those securities.

Examples of the types of securities in which the Fund would typically invest and how they are classified within this hierarchy are as follows. Typical Level 1 securities include exchange traded domestic equities, mutual funds whose net asset values are published each day and exchange traded foreign equities that are not typically statistically fair valued. Typical Level 2 securities include exchange traded foreign equities that are traded in the European region or Asia Pacific region time zones which are typically statistically fair valued, forward foreign currency exchange contracts and short-term investments valued at amortized cost. Additionally, securities fair valued by the Investment Manager’s Valuation Committee (the Committee) that rely on significant observable inputs are also included in Level 2. Typical Level 3 securities include any security fair valued by the Committee that relies on significant unobservable inputs.

The Committee is responsible for applying the Wanger Advisors Trust Portfolio Pricing Policy and the Investment Manager’s pricing procedures (the Policies), which are approved by and subject to the oversight of the Board of Trustees.

The Committee meets as necessary, and no less frequently than quarterly, to determine fair values for securities for which market quotations are not readily available or for which the Investment Manager believes that available market quotations are unreliable. The Committee also reviews the continuing appropriateness of the Policies. In circumstances where a security has been fair valued, the Committee will also review the continuing appropriateness of the current value of the security. The Policies address, among other things: circumstances under which market quotations will be deemed readily available; selection of third party pricing vendors; appropriate pricing methodologies; events that require fair valuation and fair value techniques; circumstances under which securities will be deemed to pose a potential for stale pricing, including when securities are illiquid, restricted, or in default; and certain delegations of authority to determine fair values to the Investment Manager. The Committee may also meet to discuss additional valuation matters, which may include review of back-testing results, review of time-sensitive information or approval of other valuation related actions, and to review the appropriateness of the Policies.

The following table is a summary of the inputs used to value the Fund’s investments at June 30, 2022:

	Level 1 ($)	Level 2 ($)	Level 3 ($)	Total ($)
Investments in Securities
Common Stocks
Australia	—	19,117,535	—	19,117,535
Brazil	5,807,556	—	—	5,807,556
Canada	7,165,308	—	—	7,165,308
China	—	4,366,406	—	4,366,406
Denmark	—	11,933,091	—	11,933,091
Finland	—	4,875,363	—	4,875,363
France	—	3,562,961	—	3,562,961
Germany	—	22,680,410	—	22,680,410
Hong Kong	—	1,586,510	—	1,586,510
India	—	3,127,387	—	3,127,387

The accompanying Notes to Financial Statements are an integral part of this statement.

8	Wanger International \| Semiannual Report 2022

Table of Contents

Portfolio of Investments (continued)
June 30, 2022 (Unaudited)

Fair value measurements (continued)

	Level 1 ($)	Level 2 ($)	Level 3 ($)	Total ($)
Italy	—	16,185,104	—	16,185,104
Japan	—	52,341,273	—	52,341,273
Mexico	4,986,378	—	—	4,986,378
Netherlands	3,157,965	9,168,062	—	12,326,027
New Zealand	—	1,284,326	—	1,284,326
South Korea	—	7,466,032	—	7,466,032
Spain	—	1,544,008	—	1,544,008
Sweden	—	25,608,638	—	25,608,638
Switzerland	—	13,723,928	—	13,723,928
Taiwan	—	20,552,221	—	20,552,221
United Kingdom	—	55,302,537	—	55,302,537
United States	6,409,189	—	—	6,409,189
Vietnam	—	3,952,998	—	3,952,998
Total Common Stocks	27,526,396	278,378,790	—	305,905,186
Money Market Funds	3,565,472	—	—	3,565,472
Total Investments in Securities	31,091,868	278,378,790	—	309,470,658
Investments in Derivatives
Liability
Futures Contracts	(12,673)	—	—	(12,673)
Total	31,079,195	278,378,790	—	309,457,985

See the Portfolio of Investments for all investment classifications not indicated in the table.

The Fund’s assets assigned to the Level 2 input category are generally valued using a market approach, in which a security’s value is determined through its correlation to prices and information from observable market transactions for similar or identical assets. Foreign equities are generally valued at the last sale price on the foreign exchange or market on which they trade. The Fund may use a statistical fair valuation model, in accordance with the policy adopted by the Board of Trustees, provided by an independent third party to value securities principally traded in foreign markets in order to adjust for possible stale pricing that may occur between the close of the foreign exchanges and the time for valuation. These models take into account available market data including intraday index, ADR, and ETF movements.

Derivative instruments are valued at unrealized appreciation (depreciation).

The accompanying Notes to Financial Statements are an integral part of this statement.

Wanger International | Semiannual Report 2022

Table of Contents

Statement of Assets and Liabilities
June 30, 2022 (Unaudited)

Assets
Investments in securities, at value
Unaffiliated issuers (cost $302,685,091)	$305,905,186
Affiliated issuers (cost $3,565,197)	3,565,472
Margin deposits on:
Futures contracts	56,670
Receivable for:
Investments sold	1,532,025
Capital shares sold	1,784,573
Dividends	542,549
Securities lending income	603
Foreign tax reclaims	404,989
Expense reimbursement due from Investment Manager	435
Prepaid expenses	3,929
Total assets	313,796,431
Liabilities
Foreign currency (cost $429)	433
Payable for:
Investments purchased	584,126
Capital shares purchased	309,886
Variation margin for futures contracts	4,836
Investment advisory fee	8,454
Service fees	51,830
Administration fees	428
Trustees’ fees	294,266
Printing and Postage fees	80,103
Other expenses	37,822
Total liabilities	1,372,184
Net assets applicable to outstanding capital stock	$312,424,247
Represented by
Paid in capital	314,636,483
Total distributable earnings (loss)	(2,212,236)
Total - representing net assets applicable to outstanding capital stock	$312,424,247
Shares outstanding	18,291,418
Net asset value per share	17.08

The accompanying Notes to Financial Statements are an integral part of this statement.

10	Wanger International \| Semiannual Report 2022

Table of Contents

Statement of Operations
Six Months Ended June 30, 2022 (Unaudited)

Net investment income
Income:
Dividends — unaffiliated issuers	$4,416,396
Dividends — affiliated issuers	13,007
Income from securities lending — net	50,049
Foreign taxes withheld	(479,947)
Total income	3,999,505
Expenses:
Investment advisory fee	1,834,485
Service fees	206,388
Administration fees	94,340
Trustees’ fees	22,119
Custodian fees	51,554
Printing and postage fees	57,602
Audit fees	21,990
Legal fees	31,113
Compensation of chief compliance officer	715
Other	16,831
Total expenses	2,337,137
Fees waived or expenses reimbursed by Investment Manager and its affiliates	(16,380)
Total net expenses	2,320,757
Net investment income	1,678,748
Realized and unrealized gain (loss) — net
Net realized gain (loss) on:
Investments — unaffiliated issuers	194,038
Investments — affiliated issuers	(1,306)
Foreign currency translations	(43,468)
Futures contracts	(1,187,416)
Net realized loss	(1,038,152)
Net change in unrealized appreciation (depreciation) on:
Investments — unaffiliated issuers	(173,104,186)
Investments — affiliated issuers	343
Foreign currency translations	(46,027)
Futures contracts	(12,673)
Net change in unrealized appreciation (depreciation)	(173,162,543)
Net realized and unrealized loss	(174,200,695)
Net decrease in net assets resulting from operations	$(172,521,947)

The accompanying Notes to Financial Statements are an integral part of this statement.

Wanger International | Semiannual Report 2022

Table of Contents

Statement of Changes in Net Assets

	Six Months Ended June 30, 2022 (Unaudited)	Year Ended December 31, 2021
Operations
Net investment income	$1,678,748	$310,528
Net realized gain (loss)	(1,038,152)	66,068,938
Net change in unrealized appreciation (depreciation)	(173,162,543)	17,206,777
Net increase (decrease) in net assets resulting from operations	(172,521,947)	83,586,243
Distributions to shareholders
Net investment income and net realized gains	(65,112,561)	(10,102,706)
Total distributions to shareholders	(65,112,561)	(10,102,706)
Increase (decrease) in net assets from capital stock activity	57,315,416	(48,551,559)
Total increase (decrease) in net assets	(180,319,092)	24,931,978
Net assets at beginning of period	492,743,339	467,811,361
Net assets at end of period	$312,424,247	$492,743,339

	Six Months Ended		Year Ended
	June 30, 2022 (Unaudited)		December 31, 2021
	Shares	Dollars ($)	Shares	Dollars ($)
Capital stock activity

Subscriptions	423,102	9,759,581	183,809	5,554,342
Distributions reinvested	3,465,277	65,112,561	329,784	10,102,706
Redemptions	(702,199)	(17,556,726)	(2,096,249)	(64,208,607)
Total net increase (decrease)	3,186,180	57,315,416	(1,582,656)	(48,551,559)

The accompanying Notes to Financial Statements are an integral part of this statement.

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Financial Highlights

The following table is intended to help you understand the Fund’s financial performance. Certain information reflects financial results for a single share held for the periods shown. Per share net investment income (loss) amounts are calculated based on average shares outstanding during the period. Total return assumes reinvestment of all dividends and distributions, if any. Total return does not reflect payment of the expenses that apply to the variable accounts or contract charges, if any. Total return and portfolio turnover are not annualized for periods of less than one year. The portfolio turnover rate is calculated without regard to purchase and sales transactions of short-term instruments and certain derivatives, if any. If such transactions were included, the Fund’s portfolio turnover rate may be higher.

	Six Months Ended June 30, 2022 (Unaudited)	Year Ended December 31,
	Six Months Ended June 30, 2022 (Unaudited)	2021	2020	2019	2018	2017
Per share data
Net asset value, beginning of period	$32.62	$28.03	$26.00	$22.20	$30.84	$23.64
Income from investment operations:
Net investment income	0.11	0.02	0.07	0.24	0.29	0.25
Net realized and unrealized gain (loss)	(11.24)	5.21	3.31	6.08	(4.93)	7.49
Total from investment operations	(11.13)	5.23	3.38	6.32	(4.64)	7.74
Less distributions to shareholders from:
Net investment income	(0.22)	(0.17)	(0.48)	(0.20)	(0.60)	(0.34)
Net realized gains	(4.19)	(0.47)	(0.87)	(2.32)	(3.40)	(0.20)
Total distributions to shareholders	(4.41)	(0.64)	(1.35)	(2.52)	(4.00)	(0.54)
Net asset value, end of period	$17.08	$32.62	$28.03	$26.00	$22.20	$30.84
Total return	(35.36%)^(a)	18.81%	14.36%	29.99%^(a)	(17.70%)^(a)	32.91%^(a)
Ratios to average net assets
Total gross expenses^(b)	1.24%^(c)	1.20%	1.25%	1.23%	1.19%	1.16%
Total net expenses^(b)	1.23%^(c)	1.20%	1.25%	1.20%	1.13%	1.12%
Net investment income	0.89%^(c)	0.06%	0.34%	1.01%	1.03%	0.92%
Supplemental data
Portfolio turnover	19%	36%	60%	42%	47%	55%
Net assets, end of period (in thousands)	$312,424	$492,743	$467,811	$475,562	$426,359	$578,088

Notes to Financial Highlights
(a)	Had the Investment Manager and/or its affiliates not waived a portion of expenses, total return would have been reduced.
(b)	In addition to the fees and expenses that the Fund bears directly, the Fund indirectly bears a pro rata share of the fees and expenses of any other funds in which it invests, if any. Such indirect expenses are not included in the Fund’s reported expense ratios.
(c)	Annualized.

The accompanying Notes to Financial Statements are an integral part of this statement.

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Notes to Financial Statements
June 30, 2022 (Unaudited)

Note 1. Organization

Wanger International (the Fund), a series of Wanger Advisors Trust (the Trust), is registered under the Investment Company Act of 1940, as amended (the 1940 Act), as an open-end management investment company organized as a Massachusetts business trust. The investment objective of the Fund is to seek long-term capital appreciation. The Fund is available only for allocation to certain life insurance company separate accounts established for the purpose of funding participating variable annuity contracts and variable life insurance policies and may also be offered directly to certain qualified pension and retirement plans.

Note 2. Summary of significant accounting policies

Basis of preparation

The Fund is an investment company that applies the accounting and reporting guidance in the Financial Accounting Standards Board (FASB) Accounting Standards Codification Topic 946, Financial Services - Investment Companies (ASC 946). The financial statements are prepared in accordance with U.S. generally accepted accounting principles (GAAP), which requires management to make certain estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of income and expenses during the reporting period. Actual results could differ from those estimates.

The following is a summary of significant accounting policies followed by the Fund in the preparation of its financial statements.

Security valuation

Securities of the Fund are valued at market value or, if a market quotation for a security is not readily available or is deemed not to be reliable because of events or circumstances that have occurred between the market quotation and the time as of which the security is to be valued, the security is valued at a fair value determined in good faith under consistently applied procedures established by the Board of Trustees. Equity securities listed on an exchange are valued at the closing price or last trade on their primary exchange at the close of business of the New York Stock Exchange. Securities with a closing price not readily available or not listed on any exchange are valued at the mean between the closing bid and ask prices. Listed preferred stocks convertible into common stocks are valued using an evaluated price from a pricing service.

Foreign equity securities are valued based on the closing price or last trade on their primary exchange at the close of business of the New York Stock Exchange. Foreign currency exchange rates are determined at the scheduled closing time of the New York Stock Exchange. Many securities markets and exchanges outside the U.S. close prior to the close of the New York Stock Exchange; therefore, the closing prices for securities in such markets or on such exchanges may not fully reflect events that occur after such close but before the close of the New York Stock Exchange. In situations where foreign markets are closed, where a significant event has occurred after the foreign exchange closes but before the time at which the Fund’s share price is calculated, and in the event of significant movement in the trigger index for the statistical fair valuation process established by the Board of Trustees, foreign securities will be fair valued pursuant to a policy adopted by the Board of Trustees. Under the policy, the Fund may use an independent statistical fair value pricing service that employs a systematic methodology to assist in the fair valuation process for securities principally traded in a foreign market in order to adjust for possible changes in value that may occur between the close of the foreign market and the time as of which the securities are to be valued. If a security is valued at a fair value, that value may be different from the last quoted market price for the security.

Investments in open-end investment companies (other than exchange-traded funds (ETFs)), are valued at the latest net asset value reported by those companies as of the valuation time.

Futures and options on futures contracts are valued based upon the settlement price at the close of regular trading on their principal exchanges or, in the absence of a settlement price, at the mean of the latest quoted bid and ask prices.

GAAP requires disclosure regarding the inputs and valuation techniques used to measure fair value and any changes in valuation inputs or techniques. In addition, investments shall be disclosed by major category. This information is disclosed following the Fund’s Portfolio of Investments.

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Notes to Financial Statements (continued)
June 30, 2022 (Unaudited)

Fund share valuation

Fund shares are sold and redeemed on a continuing basis at net asset value. Net asset value per share is determined daily as of the close of trading on the New York Stock Exchange on each day the New York Stock Exchange is open for trading by dividing the total value of the Fund’s investments and other assets, less liabilities, by the number of Fund shares outstanding.

Foreign currency transactions and translations

Values of investments denominated in foreign currencies are converted into U.S. dollars using the New York spot market rate of exchange at the time of valuation. Purchases and sales of investments and dividend and interest income are translated into U.S. dollars using the spot market rate of exchange prevailing on the respective dates of such transactions. The gain or loss resulting from changes in foreign exchange rates is included with net realized and unrealized gain or loss from investments, as appropriate.

Derivative instruments

The Fund invests in certain derivative instruments, as detailed below, in seeking to meet its investment objectives. Derivatives are instruments whose values depend on, or are derived from, in whole or in part, the value of one or more securities, currencies, commodities, indices, or other assets or instruments. Derivatives may be used to increase investment flexibility (including to maintain cash reserves while maintaining desired exposure to certain assets), for risk management (hedging) purposes, to facilitate trading, to reduce transaction costs and to pursue higher investment returns. The Fund may also use derivative instruments to mitigate certain investment risks, such as foreign currency exchange rate risk, interest rate risk and credit risk. Derivatives may involve various risks, including the potential inability of the counterparty to fulfill its obligations under the terms of the contract, the potential for an illiquid secondary market (making it difficult for the Fund to sell or terminate, including at favorable prices) and the potential for market movements which may expose the Fund to gains or losses in excess of the amount shown in the Statement of Assets and Liabilities. The notional amounts of derivative instruments, if applicable, are not recorded in the financial statements.

A derivative instrument may suffer a marked-to-market loss if the value of the contract decreases due to an unfavorable change in the market rates or values of the underlying instrument. Losses can also occur if the counterparty does not perform its obligations under the contract. The Fund’s risk of loss from counterparty credit risk on over-the-counter derivatives is generally limited to the aggregate unrealized gain netted against any collateral held by the Fund and the amount of any variation margin held by the counterparty, plus any replacement costs or related amounts. With exchange-traded or centrally cleared derivatives, there is reduced counterparty credit risk to the Fund since the clearinghouse or central counterparty (CCP) provides some protection in the case of clearing member default. The clearinghouse or CCP stands between the buyer and the seller of the contract; therefore, failure of the clearinghouse or CCP may pose additional counterparty credit risk. However, credit risk still exists in exchange-traded or centrally cleared derivatives with respect to initial and variation margin that is held in a broker’s customer account. While clearing brokers are required to segregate customer margin from their own assets, in the event that a clearing broker becomes insolvent or goes into bankruptcy and at that time there is a shortfall in the aggregate amount of margin held by the clearing broker for all its clients and such shortfall is remedied by the CCP or otherwise, U.S. bankruptcy laws will typically allocate that shortfall on a pro-rata basis across all the clearing broker’s customers (including the Fund), potentially resulting in losses to the Fund.

In order to better define its contractual rights and to secure rights that will help the Fund mitigate its counterparty risk, the Fund may enter into an International Swaps and Derivatives Association, Inc. Master Agreement (ISDA Master Agreement) or similar agreement with its derivatives counterparties. An ISDA Master Agreement is an agreement between the Fund and a counterparty that governs over-the-counter derivatives and foreign exchange forward contracts and contains, among other things, collateral posting terms and netting provisions in the event of a default and/or termination event. Under an ISDA Master Agreement, the Fund may, under certain circumstances, offset with the counterparty certain derivative instruments’ payables and/or receivables with collateral held and/or posted and create one single net payment. The provisions of the ISDA Master Agreement typically permit a single net payment in the event of default (close-out netting), including the bankruptcy or insolvency of the counterparty. Note, however, that bankruptcy or insolvency laws of a particular jurisdiction may impose restrictions on or prohibitions against the right of offset or netting in bankruptcy, insolvency or other events.

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Notes to Financial Statements (continued)
June 30, 2022 (Unaudited)

Collateral (margin) requirements differ by type of derivative. Margin requirements are established by the clearinghouse or CCP for exchange-traded and centrally cleared derivatives. Brokers can ask for margin in excess of the minimum in certain circumstances. Collateral terms for most over-the-counter derivatives are subject to regulatory requirements to exchange variation margin with trading counterparties and may have contract specific margin terms as well. For over-the-counter derivatives traded under an ISDA Master Agreement, the collateral requirements are typically calculated by netting the marked-to-market amount for each transaction under such agreement and comparing that amount to the value of any variation margin currently pledged by the Fund and/or the counterparty. Generally, the amount of collateral due from or to a party has to exceed a minimum transfer amount threshold (e.g., $250,000) before a transfer has to be made. To the extent amounts due to the Fund from its counterparties are not fully collateralized, contractually or otherwise, the Fund bears the risk of loss from counterparty nonperformance. The Fund may also pay interest expense on cash collateral received from the broker. Any interest expense paid by the Fund is shown in the Statement of Operations. The Fund attempts to mitigate counterparty risk by only entering into agreements with counterparties that it believes have the financial resources to honor their obligations and by monitoring the financial stability of those counterparties.

Certain ISDA Master Agreements allow counterparties of over-the-counter derivatives transactions to terminate derivatives contracts prior to maturity in the event the Fund’s net asset value declines by a stated percentage over a specified time period or if the Fund fails to meet certain terms of the ISDA Master Agreement, which would cause the Fund to accelerate payment of any net liability owed to the counterparty. The Fund also has termination rights if the counterparty fails to meet certain terms of the ISDA Master Agreement. In determining whether to exercise such termination rights, the Fund would consider, in addition to counterparty credit risk, whether termination would result in a net liability owed from the counterparty.

For financial reporting purposes, the Fund does not offset derivative assets and derivative liabilities that are subject to netting arrangements in the Statement of Assets and Liabilities.

Futures contracts

Futures contracts are exchange-traded and represent commitments for the future purchase or sale of an asset at a specified price on a specified date. During the six months ended June 30, 2022, the Fund bought and sold futures contracts to maintain appropriate equity market exposure while keeping sufficient cash to accommodate daily operations. These instruments may be used for other purposes in future periods. Upon entering into futures contracts, the Fund bears risks that it may not achieve the anticipated benefits of the futures contracts and may realize a loss. Additional risks include counterparty credit risk, the possibility of an illiquid market, and that a change in the value of the contract or option may not correlate with changes in the value of the underlying asset.

Upon entering into a futures contract, the Fund deposits cash or securities with the broker, known as a futures commission merchant (FCM), in an amount sufficient to meet the initial margin requirement. The initial margin deposit must be maintained at an established level over the life of the contract. Cash deposited as initial margin is recorded in the Statement of Assets and Liabilities as margin deposits. Securities deposited as initial margin are designated in the Portfolio of Investments. Subsequent payments (variation margin) are made or received by the Fund each day. The variation margin payments are equal to the daily change in the contract value and are recorded as variation margin receivable or payable and are offset in unrealized gains or losses. The Fund generally expects to earn interest income on its margin deposits. The Fund recognizes a realized gain or loss when the contract is closed or expires. Futures contracts involve, to varying degrees, risk of loss in excess of the variation margin disclosed in the Statement of Assets and Liabilities.

Effects of derivative transactions in the financial statements

The following tables are intended to provide additional information about the effect of derivatives on the financial statements of the Fund, including: the fair value of derivatives by risk category and the location of those fair values in the Statement of Assets and Liabilities; and the impact of derivative transactions over the period in the Statement of Operations, including realized and unrealized gains (losses). The derivative instrument schedules following the Portfolio of Investments present additional information regarding derivative instruments outstanding at the end of the period, if any.

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Notes to Financial Statements (continued)
June 30, 2022 (Unaudited)

The following table is a summary of the fair value of derivative instruments (not considered to be hedging instruments for accounting disclosure purposes) at June 30, 2022:

	Liability derivatives
Risk exposure category	Statement of assets and liabilities location	Fair value ($)
Equity risk	Component of total distributable earnings (loss) — unrealized depreciation on futures contracts	12,673*

*	Includes cumulative appreciation (depreciation) as reported in the tables following the Portfolio of Investments. Only the current day’s variation margin is reported in receivables or payables in the Statement of Assets and Liabilities.

The following table indicates the effect of derivative instruments (not considered to be hedging instruments for accounting disclosure purposes) in the Statement of Operations for the six months ended June 30, 2022:

Amount of realized gain (loss) on derivatives recognized in income
Risk exposure category	Futures contracts ($)
Equity risk	(1,187,416)

Change in unrealized appreciation (depreciation) on derivatives recognized in income
Risk exposure category	Futures contracts ($)
Equity risk	(12,673)

The following table is a summary of the average outstanding volume by derivative instrument for the six months ended June 30, 2022:

Derivative instrument	Average notional amounts ($)*
Futures contracts — long	3,834,870

*	Based on the ending quarterly outstanding amounts for the six months ended June 30, 2022.

Securities lending

The Fund may lend securities up to one-third of the value of its total assets to certain approved brokers, dealers, banks and or other institutional borrowers of securities that the Funds’ securities lending agent has determined are credit worthy under guidelines established by the Board of Trustees, to earn additional income. The Fund retains the benefits of owning the securities, including the economic equivalent of dividends or interest generated by the security. The Fund also receives a fee for the loan. The Fund has the ability to recall the loans at any time and could do so in order to vote proxies or to sell the loaned securities. Each loan is collateralized by cash that exceeded the value of the securities on loan. The market value of the loaned securities is determined daily at the close of business of the Fund and any additional required collateral is delivered to the Fund on the next business day. The Fund typically invests the cash collateral in the Dreyfus Government Cash Management Fund, a third-party institutional government money market fund in accordance with investment guidelines contained in the securities lending agreement and approved by the Board of Trustees. The income earned from the securities lending program is paid to the Fund, net of any fees remitted to Goldman Sachs Agency Lending, the Fund’s lending agent, and borrower rebates. The Fund’s investment manager, Columbia Wanger Asset Management, LLC (the Investment Manager or CWAM), does not retain any fees earned by the lending program. Generally, in the event of borrower default, the Fund has the right to use the collateral to offset any losses incurred. In the event the Fund is delayed or prevented from exercising its right to dispose of the collateral, there may be a potential loss to the Fund. Some of these losses may be indemnified by the lending agent. The Fund bears the risk of loss with respect to the investment of collateral. The net lending income earned by the Fund as of June 30, 2022, is included in the Statement of Operations.

The Fund had no outstanding loan balances as of June 30, 2022.

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Notes to Financial Statements (continued)
June 30, 2022 (Unaudited)

Security transactions and investment income

Security transactions are accounted for on the trade date (date the order to buy or sell is executed) and dividend income is recorded on the ex-dividend date, except that certain dividends from foreign securities are recorded as soon as the information is available to the Fund. Interest income is recorded on the accrual basis and includes amortization of discounts on debt obligations when required for federal income tax purposes. Realized gains and losses from security transactions are recorded on an identified cost basis.

Income recognition

Corporate actions and dividend income are generally recorded net of any non-reclaimable tax withholdings, on the ex-dividend date or upon receipt of an ex-dividend notification in the case of certain foreign securities.

The Fund may receive distributions from holdings in equity securities, exchange traded funds (ETFs), limited partnerships (LPs), other regulated investment companies (RICs), and real estate investment trusts (REITs), which report information as to the tax character of their distributions annually. These distributions are allocated to dividend income, capital gain and return of capital based on actual information reported. Return of capital is recorded as a reduction of the cost basis of securities held. If the Fund no longer owns the applicable securities, return of capital is recorded as a realized gain. With respect to REITs, to the extent actual information has not yet been reported, estimates for return of capital may be made by the Fund’s management. Management’s estimates are subsequently adjusted when the actual character of the distributions is disclosed by the REITs, which could result in a proportionate change in return of capital to shareholders.

Awards, if any, from class action litigation related to securities owned may be recorded as a reduction of cost of those securities. If the applicable securities are no longer owned, the proceeds are recorded as realized gains.

Expenses

General expenses of the Trust are allocated to the Fund and the other series of the Trust based upon relative net assets or other expense allocation methodologies determined by the nature of the expense. Expenses directly attributable to the Fund are charged to the Fund.

Federal income tax status

The Fund intends to comply with the provisions of the Internal Revenue Code available to regulated investment companies and, in the manner provided therein, intends to distribute substantially all its taxable income, as well as any net realized gain on sales of investments and foreign currency transactions reportable for federal income tax purposes. Accordingly, the Fund paid no federal income taxes and no federal income tax provision was required. The Fund meets the exception under Internal Revenue Code Section 4982(f) and the Fund expects not to be subject to federal excise tax.

Foreign taxes

The Fund may be subject to foreign taxes on income, gains on investments or currency repatriation, a portion of which may be recoverable. The Fund will accrue such taxes and recoveries, as applicable, based upon its current interpretation of tax rules and regulations that exist in the markets in which it invests.

Realized gains in certain countries may be subject to foreign taxes at the Fund level, based on statutory rates. The Fund accrues for such foreign taxes on realized and unrealized gains at the appropriate rate for each jurisdiction, as applicable. The amount, if any, is disclosed as a liability in the Statement of Assets and Liabilities.

Distributions to shareholders

Distributions to shareholders are recorded on the ex-dividend date.

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Notes to Financial Statements (continued)
June 30, 2022 (Unaudited)

Guarantees and indemnification

In the normal course of business, the Trust on behalf of the Fund enters into contracts that contain a variety of representations and warranties and that provide general indemnities. The Fund’s maximum exposure under these arrangements is unknown, as this would involve future claims against the Fund. Also under the Trust’s organizational documents, the trustees and officers of the Trust are indemnified against certain liabilities that may arise out of their duties to the Trust. However, based on experience, the Fund expects the risk of loss due to these warranties and indemnities to be remote.

Note 3. Fees and other transactions with affiliates

Management services fees

CWAM is a wholly owned subsidiary of Columbia Management Investment Advisers, LLC (Columbia Management), which in turn is a wholly owned subsidiary of Ameriprise Financial, Inc. (Ameriprise Financial). CWAM furnishes continuing investment supervision to the Fund and is responsible for the overall management of the Fund’s business affairs.

CWAM receives a monthly advisory fee based on the Fund’s daily net assets at the following annual rates:

Average daily net assets	Annual fee rate
Up to $100 million	1.10%
$100 million to $250 million	0.95%
$250 million to $500 million	0.90%
$500 million to $1 billion	0.80%
$1 billion and over	0.72%

For the six months ended June 30, 2022, the annualized effective investment advisory fee rate was 0.97% of the Fund’s average daily net assets.

Administration fees

CWAM provides administrative services and receives an administration fee from the Fund at the following annual rates:

Aggregate average daily net assets of the Trust	Annual fee rate
Up to $4 billion	0.05%
$4 billion to $6 billion	0.04%
$6 billion to $8 billion	0.03%
$8 billion and over	0.02%

For the six months ended June 30, 2022, the annualized effective administration fee rate was 0.05% of the Fund’s average daily net assets. CWAM has delegated to Columbia Management responsibility to provide certain sub-administrative services to the Fund.

Compensation of board members

Members of the Board of Trustees who are not officers or employees of the Investment Manager or Ameriprise Financial are compensated for their services to the Fund as disclosed in the Statement of Operations. Under a Deferred Compensation Plan (the Deferred Plan), these members of the Board of Trustees may elect to defer payment of up to 100% of their compensation. Deferred amounts are treated as though equivalent dollar amounts had been invested in shares of certain funds managed by the Investment Manager. The Fund’s liability for these amounts is adjusted for market value changes and remains in the Fund until distributed in accordance with the Deferred Plan. All amounts payable under the Deferred Plan constitute a general unsecured obligation of the Fund. The expense for the Deferred Plan, which includes Trustees’ fees deferred during the current period as well as any gains or losses on the Trustees’ deferred compensation balances as a result of market fluctuations, is included in "Trustees’ fees" in the Statement of Operations.

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Notes to Financial Statements (continued)
June 30, 2022 (Unaudited)

Compensation of Chief Compliance Officer

The Board of Trustees has appointed a Chief Compliance Officer for the Fund in accordance with federal securities regulations. As disclosed in the Statement of Operations, a portion of the Chief Compliance Officer’s total compensation is allocated to the Fund, along with other allocations to affiliated registered investment companies managed by the Investment Manager and its affiliates, based on relative net assets.

Service fees

Pursuant to the Transfer, Dividend Disbursing and Shareholder Servicing Agreement between the Fund and Columbia Management Investment Services Corp. (the Transfer Agent), an affiliate of the Investment Manager and a wholly-owned subsidiary of Ameriprise Financial, the Fund bears a service fee paid to the Transfer Agent to compensate it for amounts paid to Participating Insurance Companies and other financial intermediaries (together, Participating Organizations) for various sub-transfer agency and other shareholder services each Participating Organization provides to its clients, customers and participants that are invested directly or indirectly in the Fund, up to a cap approved by the Board of Trustees from time to time.

The Transfer Agent may retain as compensation for its services revenues from fees for wire, telephone and redemption orders, account transcripts due to the Transfer Agent from Fund shareholders and interest (net of bank charges) earned with respect to balances in accounts the Transfer Agent maintains in connection with its services to the Fund.

Distributor

Columbia Management Investment Distributors, Inc., a wholly owned subsidiary of Ameriprise Financial, serves as the Fund’s distributor and principal underwriter.

Other expenses waived/reimbursed by the Investment Manager and its affiliates

Through April 30, 2023, CWAM has contractually agreed to bear a portion of the Fund’s expenses so that its ordinary operating expenses (excluding transaction costs and certain other investment-related expenses, interest and fees on borrowings and expenses associated with the Fund’s investment in other investment companies, if any), do not exceed the annual rate of 1.23% of the Fund’s average daily net assets. This agreement is an extension of the arrangement that was previously in place through April 30, 2022. It may not be modified or terminated, without approval from the Fund’s Board of Trustees and CWAM. There is no guarantee that this agreement will continue after April 30, 2023.

Note 4. Federal tax information

The timing and character of income and capital gain distributions are determined in accordance with income tax regulations, which may differ from GAAP because of temporary or permanent book to tax differences.

At June 30, 2022, the approximate cost of all investments for federal income tax purposes and the aggregate gross approximate unrealized appreciation and depreciation based on that cost was:

Federal tax cost ($)	Gross unrealized appreciation ($)	Gross unrealized (depreciation) ($)	Net unrealized appreciation ($)
306,250,000	49,203,000	(45,995,000)	3,208,000

Tax cost of investments and unrealized appreciation/(depreciation) may also include timing differences that do not constitute adjustments to tax basis.

Management is required to determine whether a tax position of the Fund is more likely than not to be sustained upon examination by the applicable taxing authority, including resolution of any related appeals or litigation processes, based on the technical merits of the position. The tax benefit to be recognized by the Fund is measured as the largest amount of benefit that is greater than fifty percent likely of being realized upon ultimate settlement. Management is not aware of any tax positions in the Fund for which it is reasonably possible that the total amounts of unrecognized tax benefits will significantly change in the next twelve months. However, management’s conclusions may be subject to review and adjustment at a later

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Notes to Financial Statements (continued)
June 30, 2022 (Unaudited)

date based on factors including, but not limited to, new tax laws, regulations, and administrative interpretations (including relevant court decisions). The Fund’s federal tax returns for the prior three fiscal years remain subject to examination by the Internal Revenue Service.

Note 5. Portfolio information

The aggregate cost of purchases and proceeds from sales other than short-term obligations for the six months ended June 30, 2022, were $71,627,404 and $81,551,464, respectively. The amount of purchase and sales activity impacts the portfolio turnover rate reported in the Financial Highlights.

Note 6. Affiliated money market fund

The Fund invests in Columbia Short-Term Cash Fund, an affiliated money market fund established for the exclusive use by the Fund and other affiliated funds (the Affiliated MMF). The income earned by the Fund from such investments is included as Dividends - affiliated issuers in the Statement of Operations. As an investing fund, the Fund indirectly bears its proportionate share of the expenses of the Affiliated MMF. The Affiliated MMF prices its shares with a floating net asset value. In addition, the Board of Trustees of the Affiliated MMF may impose a fee on redemptions (sometimes referred to as a liquidity fee) or temporarily suspend redemptions (sometimes referred to as imposing a redemption gate) in the event its liquidity falls below regulatory limits.

Note 7. Line of credit

The Fund has access to a revolving credit facility with a syndicate of banks led by JPMorgan Chase Bank, N.A., Citibank, N.A. and Wells Fargo Bank, N.A. whereby the Fund may borrow for the temporary funding of shareholder redemptions or for other temporary or emergency purposes. Pursuant to an October 28, 2021 amendment and restatement, the credit facility, which is an agreement between the Fund and certain other funds managed by the Investment Manager or an affiliated investment manager, severally and not jointly, permits aggregate borrowings up to $950 million. Interest is currently charged to each participating fund based on its borrowings at a rate equal to the higher of (i) the federal funds effective rate, (ii) the secured overnight financing rate plus 0.11448% and (iii) the overnight bank funding rate, plus in each case, 1.00%. Each borrowing under the credit facility matures no later than 60 days after the date of borrowing. The Fund also pays a commitment fee equal to its pro rata share of the unused amount of the credit facility at a rate of 0.15% per annum. The commitment fee is included in other expenses in the Statement of Operations. This agreement expires annually in October unless extended or renewed. Prior to the October 28, 2021 amendment and restatement, the Fund had access to a revolving credit facility with a syndicate of banks led by JPMorgan Chase Bank, N.A., Citibank, N.A. and Wells Fargo Bank, N.A. which permitted collective borrowings up to $950 million. Interest was charged to each participating fund based on its borrowings at a rate equal to the higher of (i) the federal funds effective rate, (ii) the one-month London Interbank Offered Rate (LIBOR) rate and (iii) the overnight bank funding rate, plus in each case, 1.25%.

The Fund had no borrowings during the six months ended June 30, 2022.

Note 8. Significant risks

Foreign securities and emerging market countries risk

Investing in foreign securities may involve heightened risks relative to investments in U.S. securities. Investing in foreign securities subjects the Fund to the risks associated with the issuer’s country of organization and places of business operations, including risks associated with political, regulatory, economic, social, diplomatic and other conditions or events occurring in the country or region, which may result in significant market volatility. In addition, certain foreign securities may be more volatile and less liquid than U.S. securities. Investing in emerging markets may increase these risks and expose the Fund to elevated risks associated with increased inflation, deflation or currency devaluation. To the extent that the Fund concentrates its investment exposure to any one or a few specific countries, the Fund will be particularly susceptible to the risks associated with the conditions, events or other factors impacting those countries or regions and may, therefore, have a greater risk than that of a fund that is more geographically diversified. The financial information and disclosure made available by issuers of emerging market securities may be considerably less reliable than publicly available information about other foreign securities. The Public Company Accounting Oversight Board, which regulates auditors of U.S. public companies, is

Wanger International | Semiannual Report 2022

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Notes to Financial Statements (continued)
June 30, 2022 (Unaudited)

unable to inspect audit work papers in certain foreign countries. Investors in foreign countries often have limited rights and few practical remedies to pursue shareholder claims, including class actions or fraud claims, and the ability of the U.S. Securities and Exchange Commission, the U.S. Department of Justice and other authorities to bring and enforce actions against foreign issuers or foreign persons is limited.

Geographic focus risk

The Fund may be particularly susceptible to risks related to economic, political, regulatory or other events or conditions affecting issuers and countries within the specific geographic regions in which the Fund invests. The Fund’s net asset value may be more volatile than the net asset value of a more geographically diversified fund.

Asia Pacific Region. The Fund is particularly susceptible to economic, political, regulatory or other events or conditions affecting issuers and countries in the Asia Pacific region. Many of the countries in the region are considered underdeveloped or developing, including from a political, economic and/or social perspective, and may have relatively unstable governments and economies based on limited business, industries and/or natural resources or commodities. Events in any one country within the region may impact other countries in the region or the region as a whole. As a result, events in the region will generally have a greater effect on the Fund than if the Fund were more geographically diversified. This could result in increased volatility in the value of the Fund’s investments and losses for the Fund. Also, securities of some companies in the region can be less liquid than U.S. or other foreign securities, potentially making it difficult for the Fund to sell such securities at a desirable time and price.

Europe. The Fund is particularly susceptible to risks related to economic, political, regulatory or other events or conditions, including acts of war or other conflicts in the region, affecting issuers and countries in Europe. Countries in Europe are often closely connected and interdependent, and events in one European country can have an adverse impact on, and potentially spread to, other European countries. In addition, private and public sectors’ significant debt problems of a single European Union (EU) country can pose economic risks to the EU as a whole. As a result, the Fund’s net asset value may be more volatile than the net asset value of a more geographically diversified fund. If securities of issuers in Europe fall out of favor, it may cause the Fund to underperform other funds that do not focus their investments in this region of the world. The departure of the United Kingdom (UK) from the EU single market became effective January 1, 2021 with the end of the Brexit transition period and the post-Brexit trade deal between the UK and EU taking effect on December 31, 2020. The impact of Brexit on the UK and European economies and the broader global economy could be significant, resulting in negative impacts on currency and financial markets generally, such as increased volatility and illiquidity, and potentially lower economic growth in markets in Europe, which may adversely affect the value of your investment in the Fund.

Industrials sector risk

The Fund is more susceptible to the particular risks that may affect companies in the industrials sector than if it were invested in a wider variety of companies in unrelated sectors. Companies in the industrials sector are subject to certain risks, including changes in supply and demand for their specific product or service and for industrial sector products in general, including decline in demand for such products due to rapid technological developments and frequent new product introduction. Performance of such companies may be affected by factors including government regulation, world events and economic conditions and risks for environmental damage and product liability claims.

Information technology sector risk

The Fund is more susceptible to the particular risks that may affect companies in the information technology sector than if it were invested in a wider variety of companies in unrelated sectors. Companies in the information technology sector are subject to certain risks, including the risk that new services, equipment or technologies will not be accepted by consumers and businesses or will become rapidly obsolete. Performance of such companies may be affected by factors including obtaining and protecting patents (or the failure to do so) and significant competitive pressures, including aggressive pricing of their products or services, new market entrants, competition for market share and short product cycles due to an accelerated rate of technological developments. Such competitive pressures may lead to limited earnings and/or falling profit margins. As a result, the value of their securities may fall or fail to rise. In addition, many information technology sector companies have limited operating histories and prices of these companies’ securities historically have been more volatile than other

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Notes to Financial Statements (continued)
June 30, 2022 (Unaudited)

securities, especially over the short term. Some companies in the information technology sector are facing increased government and regulatory scrutiny and may be subject to adverse government or regulatory action, which could negatively impact the value of their securities.

Market risk

The Fund may incur losses due to declines in the value of one or more securities in which it invests. These declines may be due to factors affecting a particular issuer, or the result of, among other things, political, regulatory, market, economic or social developments affecting the relevant market(s) more generally. In addition, turbulence in financial markets and reduced liquidity in equity, credit and/or fixed income markets may negatively affect many issuers, which could adversely affect the Fund’s ability to price or value hard-to-value assets in thinly traded and closed markets and could cause significant redemptions and operational challenges. Global economies and financial markets are increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. These risks may be magnified if certain events or developments adversely interrupt the global supply chain; in these and other circumstances, such risks might affect companies worldwide. As a result, local, regional or global events such as terrorism, war, natural disasters, disease/virus outbreaks and epidemics or other public health issues, recessions, depressions or other events – or the potential for such events – could have a significant negative impact on global economic and market conditions.

The large-scale invasion of Ukraine by Russia in February 2022 has resulted in sanctions and market disruptions, including declines in regional and global stock markets, unusual volatility in global commodity markets and significant devaluations of Russian currency. The extent and duration of the military action are impossible to predict but could be significant. Market disruption caused by the Russian military action, and any counter-measures or responses thereto (including international sanctions, a downgrade in the country’s credit rating, purchasing and financing restrictions, boycotts, tariffs, changes in consumer or purchaser preferences, cyberattacks and espionage) could have severe adverse impacts on regional and/or global securities and commodities markets, including markets for oil and natural gas. These impacts may include reduced market liquidity, distress in credit markets, further disruption of global supply chains, increased risk of inflation, and limited access to investments in certain international markets and/or issuers. These developments and other related events could negatively impact Fund performance.

The pandemic caused by coronavirus disease 2019 and its variants (COVID-19) has resulted in, and may continue to result in, significant global economic and societal disruption and market volatility due to disruptions in market access, resource availability, facilities operations, imposition of tariffs, export controls and supply chain disruption, among others. Such disruptions may be caused, or exacerbated by, quarantines and travel restrictions, workforce displacement and loss in human and other resources. The uncertainty surrounding the magnitude, duration, reach, costs and effects of the global pandemic, as well as actions that have been or could be taken by governmental authorities or other third parties, present unknowns that are yet to unfold. The impacts, as well as the uncertainty over impacts to come, of COVID-19 – and any other infectious illness outbreaks, epidemics and pandemics that may arise in the future – could negatively affect global economies and markets in ways that cannot necessarily be foreseen. In addition, the impact of infectious illness outbreaks and epidemics in emerging market countries may be greater due to generally less established healthcare systems, governments and financial markets. Public health crises caused by the COVID-19 outbreak may exacerbate other pre-existing political, social and economic risks in certain countries or globally. The disruptions caused by COVID-19 could prevent the Fund from executing advantageous investment decisions in a timely manner and negatively impact the Fund’s ability to achieve its investment objective. Any such events could have a significant adverse impact on the value and risk profile of the Fund.

Shareholder concentration risk

At June 30, 2022, one unaffiliated shareholder of record owned 19.2% of the outstanding shares of the Fund in one or more accounts. The Fund has no knowledge about whether any portion of those shares was owned beneficially. Affiliated shareholders of record owned 58.0% of the outstanding shares of the Fund in one or more accounts. Subscription and redemption activity by concentrated accounts may have a significant effect on the operations of the Fund. In the case of a large redemption, the Fund may be forced to sell investments at inopportune times, including its liquid positions, which may result in Fund losses and the Fund holding a higher percentage of less liquid positions. Large redemptions could result in decreased economies of scale and increased operating expenses for non-redeeming Fund shareholders.

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Notes to Financial Statements (continued)
June 30, 2022 (Unaudited)

Small- and mid-cap company risk

Investments in small- and mid-capitalization companies (small- and mid-cap companies) often involve greater risks than investments in larger, more established companies (larger companies) because small- and mid-cap companies tend to have less predictable earnings and may lack the management experience, financial resources, product diversification and competitive strengths of larger companies. Securities of small- and mid-cap companies may be less liquid and more volatile than the securities of larger companies.

Note 9. Subsequent events

Management has evaluated the events and transactions that have occurred through the date the financial statements were issued and noted no items requiring adjustment of the financial statements or additional disclosure.

Note 10. Information regarding pending and settled legal proceedings

Ameriprise Financial and certain of its affiliates are involved in the normal course of business in legal proceedings which include regulatory inquiries, arbitration and litigation, including class actions concerning matters arising in connection with the conduct of its activities as a diversified financial services firm. Ameriprise Financial believes that the Fund is not currently the subject of, and that neither Ameriprise Financial nor any of its affiliates are the subject of, any pending legal, arbitration or regulatory proceedings that are likely to have a material adverse effect on the Fund or the ability of Ameriprise Financial or its affiliates to perform under their contracts with the Fund. Ameriprise Financial is required to make quarterly (10-Q), annual (10-K) and, as necessary, 8-K filings with the Securities and Exchange Commission (SEC) on legal and regulatory matters that relate to Ameriprise Financial and its affiliates. Copies of these filings may be obtained by accessing the SEC website at www.sec.gov.

There can be no assurance that these matters, or the adverse publicity associated with them, will not result in increased Fund redemptions, reduced sale of Fund shares or other adverse consequences to the Fund. Further, although we believe proceedings are not likely to have a material adverse effect on the Fund or the ability of Ameriprise Financial or its affiliates to perform under their contracts with the Fund, these proceedings are subject to uncertainties and, as such, we are unable to estimate the possible loss or range of loss that may result. An adverse outcome in one or more of these proceedings could result in adverse judgments, settlements, fines, penalties or other relief that could have a material adverse effect on the consolidated financial condition or results of operations of Ameriprise Financial or one or more of its affiliates that provides services to the Fund.

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Liquidity Risk Management Program

(Unaudited)

Pursuant to Rule 22e-4 under the 1940 Act, the Fund has adopted a liquidity risk management program (Program). The Program’s principal objectives include assessing, managing and periodically reviewing the Fund’s liquidity risk. Liquidity risk is defined as the risk that the Fund could not meet redemption requests without significant dilution of remaining investors’ interests in the Fund.

The Board of Trustees has appointed the Investment Manager as the program administrator for the Program. The Investment Manager has delegated oversight of the Program to its Liquidity Risk Management Committee (the Committee). At a Board meeting during the fiscal period, the Committee provided the Board with a report addressing the operations of the Program and assessing its adequacy and effectiveness of implementation for the period January 1, 2021, through December 31, 2021. Among other things, the report indicated that:

•	the Fund had sufficient liquidity to both meet redemptions and operate effectively on behalf of shareholders;
•	there were no material changes to the Program during the period;
•	the Fund’s strategy continued to be effective for an open-end mutual fund;
•	the implementation of the Program was effective to manage the Fund’s liquidity risk;
•	the Fund did not require a highly liquid investment minimum; and
•	the Program operated adequately during the period.

There can be no assurance that the Program will achieve its objectives in the future. Please refer to the Fund’s prospectus for more information regarding the Fund’s exposure to liquidity risk and other principal risks to which an investment in the Fund may be subject.

Board Consideration and Approval of Advisory

Agreement

(Unaudited)

Wanger Advisors Trust (the “Trust”) has an investment advisory agreement (the “Advisory Agreement”) with Columbia Wanger Asset Management, LLC (“CWAM”) under which CWAM manages Wanger International (the “Fund”). All of the voting trustees of the Trust are persons who have no direct or indirect interest in the Advisory Agreement and are not “interested persons” (as defined in the Investment Company Act of 1940, as amended (the “1940 Act”)) of the Trust (the “Independent Trustees”). The Independent Trustees oversee the management of the Fund and, as required by law, determine at least annually whether to continue the Advisory Agreement for the Fund.

The Contract Committee (the “Contract Committee”) of the Board of Trustees of the Trust (the “Board”), which is comprised solely of Independent Trustees, makes recommendations to the Board regarding any proposed continuation of the Advisory Agreement. After the Contract Committee has made its recommendations, the full Board determines whether to approve the continuation of the Advisory Agreement. The Board also considers matters bearing on the Advisory Agreement at its various meetings throughout the year, meets at least quarterly with CWAM investment personnel (as does the Board’s Investment Performance Analysis Committee (the “Performance Committee”)), and receives monthly reports from CWAM on the performance of the Fund.

In connection with their most recent consideration of the Advisory Agreement for the Fund, the members of the Contract Committee and all Independent Trustees received and reviewed a substantial amount of information provided by CWAM, Columbia Management Investment Advisers, LLC (“Columbia Management”) and Ameriprise Financial, Inc. (“Ameriprise”), the parent of CWAM and Columbia Management, in response to written requests from the Independent Trustees and their independent legal counsel. Throughout the process, the Independent Trustees had numerous opportunities to ask questions of and request additional materials from CWAM, Columbia Management and Ameriprise.

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Board Consideration and Approval of Advisory

Agreement (continued)

(Unaudited)

During each meeting at which the Contract Committee or the Independent Trustees considered the Advisory Agreement, they met in at least one executive session with their independent legal counsel. The Contract Committee also met with representatives of CWAM, Columbia Management and Ameriprise on several occasions. In all, the Contract Committee convened formally on five separate occasions to consider the continuation of the Advisory Agreement. The Board and/or some or all of the Independent Trustees met informally on other occasions to receive the Contract Committee’s status reports and/or to discuss outstanding issues. In addition, the Performance Committee, which is also comprised exclusively of Independent Trustees, reviewed the performance of the Fund, met in joint meetings with the Contract Committee, and reported to the Board and/or the Contract Committee throughout the year. The chair of the Audit & Compliance Committee of the Board (the “Audit & Compliance Committee”) made available relevant information with respect to matters within the realm of the Audit & Compliance Committee’s oversight responsibilities.

The materials reviewed by the Contract Committee and the Independent Trustees included, among other items: (i) information on the investment performance of the Fund relative to independently selected peer groups of funds, a peer group of funds selected using a methodology chosen by Columbia Management, which included both underlying variable insurance products and institutional funds (the “Supplemental Group”) and the Fund’s performance benchmark over various time periods, as presented and analyzed by an independent consultant; (ii) information on the Fund’s advisory fees and other expenses, including information comparing the Fund’s fees and expenses to those of a peer group of funds and information about any applicable expense limitations and fee breakpoints; (iii) data on sales and redemptions of Fund shares; and (iv) information on the profitability to CWAM and its affiliates, as well as potential “fall-out” or ancillary benefits that CWAM and its affiliates may receive as a result of their relationships with the Fund. The Contract Committee and the Board also considered other information, such as: (i) CWAM’s financial condition; (ii) the Fund’s investment objective and strategy; (iii) the overall level of resources devoted to the Fund; (iv) the size, education, experience and resources of CWAM’s investment staff and its use of technology, including with respect to the liquidity risk management program and external research and trading cost measurement tools; (v) changes in investment and other personnel at CWAM; (vi) the portfolio manager compensation framework at CWAM; (vii) the allocation of the Fund’s brokerage, and the use of “soft” commission dollars to pay for research products and services; (viii) CWAM’s risk management program; (ix) the resources devoted to, and the record of compliance with, the Fund’s investment policies and restrictions, policies on personal securities transactions and other compliance policies and procedures; (x) CWAM’s and its affiliates’ conflicts of interest; and (xi) CWAM’s management of the Fund in light of market and operating conditions arising from the COVID-19 pandemic.

At a meeting held on June 8, 2022, the Board considered and unanimously approved the continuation of the Advisory Agreement. In considering the continuation of the Advisory Agreement, the Independent Trustees reviewed and analyzed various factors that they determined were relevant, none of which by itself was considered dispositive. The material factors and conclusions that formed the basis for the Independent Trustees’ determination to approve the continuation of the Advisory Agreement are discussed below.

Nature, quality and extent of services

The Independent Trustees reviewed the nature, quality and extent of the services provided by CWAM and its affiliates to the Fund under the Advisory Agreement, taking into account the investment objective and strategy of the Fund, its shareholder base and knowledge gained from meetings with management, which were held on at least a quarterly basis. They reviewed the available resources and key personnel of CWAM and its affiliates, especially those providing investment management services to the Fund. They also considered the resources dedicated specifically to CWAM by its parent company pursuant to the Advisory Agreement and the contribution of those resources to the portfolio management process. The Independent Trustees also considered other services provided to the Fund by CWAM and its affiliates, including: managing the execution of portfolio transactions and selecting broker-dealers for those transactions; monitoring adherence to the Fund’s investment restrictions; monitoring and managing the Fund’s liquidity pursuant to the liquidity risk management program; providing support services for, and regular updates on the operations of the Fund to, the Board and committees of the Board; managing the Fund’s securities lending program; communicating with shareholders; serving as the Fund’s administrator and fund accountant; and overseeing the activities of the Fund’s other service providers, including monitoring for compliance with various policies and procedures as well as applicable securities laws and regulations. The Independent Trustees also considered CWAM’s ability to operate from a remote working environment in connection with the COVID-19 pandemic without

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Board Consideration and Approval of Advisory

Agreement (continued)

(Unaudited)

any adverse impact on the Fund or shareholders. The Independent Trustees also noted the quality of CWAM’s compliance record. The Independent Trustees considered CWAM’s extensive and focused efforts to continue to improve the performance of the Fund and believed they were reasonable and appropriate.

The Independent Trustees concluded that the nature, quality and extent of the services provided by CWAM and its affiliates to the Fund under the Advisory Agreement were appropriate for the Fund and that the Fund was likely to benefit from the continued provision of those services by CWAM. They also concluded that CWAM had sufficient personnel, with appropriate education and experience, to serve the Fund effectively. The Independent Trustees also considered that Ameriprise had committed to the Board that CWAM would have sufficient investment management resources to continue to improve performance, including but not limited to resources to hire investment personnel, as necessary.

Performance of the Fund

The Independent Trustees reviewed information comparing the Fund’s performance with that of comparable funds and peer groups as identified by independent consultant Broadridge Financial Solutions, Inc. (“Broadridge”) and the performance of the Fund’s primary benchmark. They also reviewed information from Broadridge comparing the performance of the Fund with the Supplemental Group. The Independent Trustees evaluated the performance and risk characteristics of the Fund over various periods, including over the one-, three- and five-year periods ended December 31, 2021. They considered that the Fund had outperformed the median of both its Broadridge peer group and the Supplemental Group for the one-, three- and five-year periods ended December 31, 2021. The Independent Trustees also took into account that the Fund had outperformed its primary benchmark for the one-, three- and five-year periods ended December 31, 2021. In addition, the Independent Trustees considered that the Fund had underperformed its Broadridge peer group median and primary benchmark for the one-, three- and five-year periods ended April 30, 2022.

In light of this information, the Independent Trustees concluded that the Fund’s performance was satisfactory versus its peers and primary benchmark. In addition, the Independent Trustees considered that CWAM’s International Team Head and Director of International Research had reported to them at numerous Contract Committee, Performance Committee and Board meetings on measures taken over the past several years to improve the Fund’s performance.

Costs of services and profits realized by CWAM

At various Committee and Board meetings, the Independent Trustees examined detailed information on the fees and expenses of the Fund compared with information for similar funds provided by Broadridge. They also reviewed information on the fees and expenses of the Fund compared with information for funds included in the Supplemental Group. They noted that, although the Fund’s total net expenses and actual advisory fees were higher than its Broadridge peer group median, the Fund’s advisory fees were generally comparable to the advisory fees of Columbia Acorn International, as series of Columbia Acorn Trust, which was managed by CWAM similarly to the Fund, at similar asset levels. They also considered that the Fund’s total net expenses and actual advisory fees were higher than the median of the Supplemental Group.

The Independent Trustees reviewed the total expenses of the Fund relative to its three- and five-year performance, as prepared by Broadridge, in considering the total expense levels of the Fund. In addition, the Independent Trustees took into account that CWAM had contractually agreed through April 30, 2023 to limit fees and expenses so that the Fund’s total expenses did not increase versus the prior year.

The Independent Trustees took into account that CWAM did not manage other investment companies as a sub-adviser or other institutional separate accounts that had investment strategies similar to the Fund.

The Independent Trustees reviewed an analysis of CWAM’s profitability in serving as the Fund’s investment manager and of CWAM and its affiliates in their relationships with the Fund. They considered that the Contract Committee and the Board met with representatives from Ameriprise to discuss its methodologies for calculating profitability and allocating costs. They considered that Ameriprise calculated profitability and allocated costs on a contract-by-contract and fund-by-fund basis. In addition, the Independent Trustees considered an analysis of CWAM’s anticipated profitability in serving as the investment manager to the funds in the Trust and Columbia Acorn Trust at various hypothetical levels of total assets. They also reviewed

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Board Consideration and Approval of Advisory

Agreement (continued)

(Unaudited)

the methodology used by CWAM and Ameriprise to determine the level of compensation payable to portfolio managers and the competitive market for investment management talent and whether the methodology was aligned with shareholders’ interests. The Independent Trustees were provided with profitability information from a third-party consultant, Strategic Insight, which compared CWAM’s profitability to other similar investment managers in the mutual fund industry. The Independent Trustees discussed, however, that profitability comparisons among fund managers may not always be meaningful due to the lack of consistency in data, small number of publicly-owned managers, and the fact that the profitability of any investment manager is affected by numerous factors, including its particular organizational structure, the types of funds and other accounts managed, other lines of business, expense allocation methodology, capital structure and other factors. The Independent Trustees evaluated CWAM’s profitability in light of the additional resources that had been, and would continue to be, provided to the Fund by Ameriprise to assist in improving Fund performance.

Economies of scale

At various Committee and Board meetings and other informal meetings, the Independent Trustees also considered information about the extent to which CWAM realized economies of scale in connection with an increase in Fund assets. It was noted, however, that the Fund had lost assets over the past several years. The Independent Trustees noted that the advisory fee schedule for the Fund included breakpoints in the rate of fees at various asset levels. In evaluating whether CWAM was sharing economies of scale with Fund shareholders, the Independent Trustees also took into account the expense limitation or waivers that CWAM had agreed to for the Fund for 2022 and 2023. The Independent Trustees concluded that the fee structure of the Advisory Agreement for the Fund reflected a sharing of economies of scale between CWAM and the Fund.

Other benefits to CWAM

The Independent Trustees also reviewed benefits that accrued to CWAM and its affiliates from their relationships with the Fund, based upon information provided to them by Ameriprise. They noted that the Fund’s transfer agency services were performed by Columbia Management Investment Services Corp., an affiliate of Ameriprise, which received compensation from the Fund for its transfer agent services. They considered that another affiliate of Ameriprise, Columbia Management Investment Distributors, Inc., served as the Fund’s distributor under an underwriting agreement but received no fees for its services to the Fund. In addition, they considered that Columbia Management provided sub-administration services to the Fund. The Contract Committee and the Board received information regarding the profitability of these Fund agreements to the CWAM affiliates and also reviewed information about and discussed the capabilities of each affiliated entity in performing its respective duties.

The Independent Trustees considered other ways that the Fund and CWAM might potentially benefit from their relationship with each other. For example, the Independent Trustees considered CWAM’s use of commissions paid by the Fund on its portfolio brokerage transactions to obtain research products and services benefiting the Fund and/or other clients of CWAM. They noted that the Audit & Compliance Committee reviewed CWAM’s annual “soft dollar” report during the year and met with representatives from CWAM to review CWAM’s soft dollar spending. The Independent Trustees also considered that the Audit & Compliance Committee and/or Board regularly reviewed third-party prepared reports that evaluated the quality of CWAM’s execution of the Fund’s portfolio transactions. The Independent Trustees determined that CWAM’s use of the Fund’s “soft” commission dollars to obtain research products and services was consistent with current regulatory requirements and guidance. They also concluded that CWAM benefitted from the receipt of proprietary research products and services acquired through commissions paid on portfolio transactions of the Fund, and that the Fund benefitted from CWAM’s receipt of those products and services as well as research products and services acquired through commissions paid by other clients of CWAM.

After full consideration of the above factors, as well as other factors that were instructive in evaluating the Advisory Agreement, the Independent Trustees concluded that the advisory fees were reasonable and that the continuation of the Advisory Agreement was in the best interest of the Fund. At the Board meeting held on June 8, 2022, the Independent Trustees approved the continuation of the Advisory Agreement for the Fund through July 31, 2023.

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Table of Contents

Fund at a Glance	3
Understanding Your Fund’s Expenses	5
Portfolio of Investments	6
Statement of Assets and Liabilities	10
Statement of Operations	11
Statement of Changes in Net Assets	12
Financial Highlights	13
Notes to Financial Statements	14
Liquidity Risk Management Program	22
Board Consideration and Approval of Advisory Agreement	22

Proxy voting policies and procedures

The policy of the Board of Trustees is to vote the proxies of the companies in which Wanger Acorn (the Fund) holds investments consistent with the procedures as stated in the Statement of Additional Information (SAI). You may obtain a copy of the SAI without charge by calling 800.345.6611; contacting your financial intermediary; visiting columbiathreadneedleus.com/investor/; or searching the website of the Securities and Exchange Commission (SEC) at sec.gov. Information regarding how the Fund voted proxies relating to portfolio securities is filed with the SEC by August 31st for the most recent 12-month period ending June 30th of that year, and is available without charge by visiting columbiathreadneedleus.com/investor/, or searching the website of the SEC at sec.gov.

Quarterly schedule of investments

Additional Fund information

Fund investment manager

Columbia Wanger Asset Management, LLC (the Investment Manager)

71 S Wacker Drive, Suite 2500

Chicago, IL 60606

888.4.WANGER

(888.492.6437)

Fund distributor

Columbia Management Investment Distributors, Inc.

290 Congress Street

Boston, MA 02210

Fund transfer agent

Columbia Management Investment Services Corp.

P.O. Box 219104

Kansas City, MO 64121-9104

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Table of Contents

Fund at a Glance
(Unaudited)

Investment objective

The Fund seeks long-term capital appreciation.

Portfolio management

Daniel Cole, CFA

Co-Portfolio Manager since May 2022

Service with the Fund since 2021

Erika K. Maschmeyer, CFA

Co-Portfolio Manager since 2021

Service with the Fund since 2016

John L. Emerson, CFA

Co-Portfolio Manager since 2021

Service with the Fund since 2003

Average annual total returns (%) (for the period ended June 30, 2022)
	Inception	6 Months cumulative	1 Year	5 Years	10 Years	Life of Fund
Wanger Acorn	05/03/95	-36.32	-36.86	3.61	8.65	10.23
Russell 2500 Growth Index		-29.45	-31.81	7.53	10.88	-
Russell 2000 Growth Index		-29.45	-33.43	4.80	9.30	-

The Fund’s annual operating expense ratio of 0.95% is stated as of the Fund’s prospectus dated May 1, 2022, and differences in expense ratios disclosed elsewhere in this report may result from the reflection of fee waivers and/or expense reimbursements as well as different time periods used in calculating the ratios.

All results shown assume reinvestment of distributions.

The Russell 2500 Growth Index measures the performance of those Russell 2500 companies with higher price-to-book ratios and higher forecasted growth values.

The Russell 2000 Growth Index, an unmanaged index, measures the performance of those Russell 2000 Index companies with higher price-to-book ratios and higher forecasted growth values.

Effective May 1, 2022, the Fund increased the market capitalization range of the companies in which it invests a majority of its assets and began comparing its performance to that of the Russell 2500 Growth Index. The Investment Manager believes that the Russell 2500 Growth Index provides a more appropriate comparison than the Russell 2000 Growth Index for investors measuring the Fund’s relative performance. Information on both the Russell 2000 Growth Index and the Russell 2500 Growth Index will be shown for a one-year transition period. The Fund’s performance prior to May 1, 2022 reflects returns achieved pursuant to a strategy with a different market capitalization limit on the companies in which the Fund invests a majority of its assets. If the Fund’s current strategies had been in place for the prior periods, results shown would have been different.

Indexes are not managed and do not incur fees or expenses. It is not possible to invest directly in an index.

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Understanding Your Fund’s Expenses
(Unaudited)

As a shareholder, you incur three types of costs. There are shareholder transaction costs, which may include redemption fees. There are also ongoing fund costs, which generally include investment advisory fees and other expenses for Wanger Acorn (the Fund). Lastly, there may be additional fees or charges imposed by the insurance company that sponsors your variable annuity and/or variable life insurance product. The following information is intended to help you understand your ongoing costs (in dollars) of investing in the Fund and to help you compare these costs with the ongoing costs of investing in other mutual funds.

Analyzing your Fund’s expenses

Compare with other funds

January 1, 2022 — June 30, 2022
	Account value at the beginning of the period ($)		Account value at the end of the period ($)		Expenses paid during the period ($)		Fund’s annualized expense ratio (%)
	Actual	Hypothetical	Actual	Hypothetical	Actual	Hypothetical	Actual
Wanger Acorn	1,000.00	1,000.00	636.80	1,019.49	4.34	5.36	1.07

Effective May 1, 2022, the advisory fee is an annual fee that is equal to a percentage of the Fund’s average daily net assets that declines from 0.74% to 0.63% as the Fund’s net assets increase. If this change had been in place for the entire six month period ended June 30, 2022, the annualized effective advisory fee rate would have been 0.74%. The actual expenses paid would have been $3.98 and the hypothetical expenses paid would have been $4.91.

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Table of Contents

Portfolio of Investments
June 30, 2022 (Unaudited)

(Percentages represent value of investments compared to net assets)

Investments in securities

Common Stocks 96.3%
Issuer	Shares	Value ($)
Communication Services 2.5%
Entertainment 2.5%
Roblox Corp., Class A^(a)	75,293	2,474,128
Take-Two Interactive Software, Inc.^(a)	64,054	7,848,537
Total		10,322,665
Total Communication Services		10,322,665
Consumer Discretionary 15.6%
Auto Components 1.2%
Dorman Products, Inc.^(a)	45,551	4,997,400
Diversified Consumer Services 2.3%
Bright Horizons Family Solutions, Inc.^(a)	50,021	4,227,775
Chegg, Inc.^(a)	280,537	5,268,485
Total		9,496,260
Hotels, Restaurants & Leisure 5.9%
Churchill Downs, Inc.	35,431	6,786,100
Planet Fitness, Inc., Class A^(a)	131,591	8,949,504
Wingstop, Inc.	121,081	9,053,226
Total		24,788,830
Household Durables 2.1%
Skyline Champion Corp.^(a)	188,247	8,926,673
Internet & Direct Marketing Retail 0.8%
Etsy, Inc.^(a)	45,387	3,322,782
Specialty Retail 3.3%
Five Below, Inc.^(a)	59,665	6,767,801
Floor & Decor Holdings, Inc.^(a)	43,612	2,745,811
Williams-Sonoma, Inc.	41,207	4,571,917
Total		14,085,529
Total Consumer Discretionary		65,617,474
Consumer Staples 3.1%
Food & Staples Retailing 1.4%
BJ’s Wholesale Club Holdings, Inc.^(a)	95,710	5,964,647
Household Products 1.7%
WD-40 Co.	36,117	7,272,519
Total Consumer Staples		13,237,166

Common Stocks (continued)
Issuer	Shares	Value ($)
Energy 2.8%
Oil, Gas & Consumable Fuels 2.8%
Antero Resources Corp.^(a)	54,716	1,677,045
Devon Energy Corp.	91,387	5,036,338
Diamondback Energy, Inc.	40,103	4,858,478
Total		11,571,861
Total Energy		11,571,861
Financials 4.3%
Banks 1.1%
Lakeland Financial Corp.	71,553	4,752,550
Capital Markets 2.7%
Ares Management Corp., Class A	81,593	4,639,378
GCM Grosvenor, Inc., Class A	507,903	3,479,136
Houlihan Lokey, Inc., Class A	43,726	3,451,293
Total		11,569,807
Insurance 0.5%
Ryan Specialty Holdings, Inc., Class A^(a)	50,076	1,962,478
Total Financials		18,284,835
Health Care 19.3%
Biotechnology 3.2%
Argenx SE, ADR^(a)	8,536	3,234,120
Insmed, Inc.^(a)	131,507	2,593,318
Intellia Therapeutics, Inc.^(a)	28,563	1,478,421
Iovance Biotherapeutics, Inc.^(a)	101,563	1,121,256
Natera, Inc.^(a)	147,944	5,243,135
Total		13,670,250
Health Care Equipment & Supplies 2.8%
Axonics, Inc.^(a)	63,080	3,574,744
Insulet Corp.^(a)	37,959	8,272,784
Total		11,847,528
Health Care Providers & Services 4.1%
Amedisys, Inc.^(a)	62,004	6,517,861
Chemed Corp.	19,578	9,189,717
P3 Health Partners, Inc., Class A^(a),(b)	384,629	1,430,820
Total		17,138,398

The accompanying Notes to Financial Statements are an integral part of this statement.

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Portfolio of Investments (continued)
June 30, 2022 (Unaudited)

Common Stocks (continued)
Issuer	Shares	Value ($)
Health Care Technology 2.1%
Doximity, Inc., Class A^(a),(b)	183,247	6,380,661
Inspire Medical Systems, Inc.^(a)	12,838	2,345,117
Total		8,725,778
Life Sciences Tools & Services 5.3%
Bio-Techne Corp.	31,981	11,085,894
DNA Script^{(a),(c),(d),(e)}	2,550	1,021,048
Repligen Corp.^(a)	62,780	10,195,472
Total		22,302,414
Pharmaceuticals 1.8%
Catalent, Inc.^(a)	71,032	7,621,023
Total Health Care		81,305,391
Industrials 18.9%
Commercial Services & Supplies 1.7%
Rollins, Inc.	206,055	7,195,441
Electrical Equipment 4.1%
AMETEK, Inc.	73,349	8,060,322
Atkore, Inc.^(a)	40,223	3,338,911
Generac Holdings, Inc.^(a)	27,668	5,826,327
Total		17,225,560
Machinery 5.8%
Ingersoll Rand, Inc.	170,402	7,170,516
Kornit Digital Ltd.^(a)	101,312	3,211,590
Middleby Corp. (The)^(a)	42,224	5,293,201
SPX Corp.^(a)	165,969	8,769,802
Total		24,445,109
Professional Services 5.2%
Booz Allen Hamilton Holdings Corp.	75,992	6,866,637
CoStar Group, Inc.^(a)	163,585	9,882,170
ICF International, Inc.	51,509	4,893,355
Total		21,642,162
Trading Companies & Distributors 2.1%
SiteOne Landscape Supply, Inc.^(a)	74,479	8,853,319
Total Industrials		79,361,591
Information Technology 24.1%
Electronic Equipment, Instruments & Components 2.1%
CDW Corp.	54,376	8,567,482

Common Stocks (continued)
Issuer	Shares	Value ($)
IT Services 4.0%
DigitalOcean Holdings, Inc.^(a),(b)	78,697	3,254,908
Endava PLC, ADR^(a)	35,523	3,135,615
MongoDB, Inc.^(a)	23,446	6,084,237
VeriSign, Inc.^(a)	25,914	4,336,190
Total		16,810,950
Semiconductors & Semiconductor Equipment 3.7%
Enphase Energy, Inc.^(a)	32,362	6,318,357
Marvell Technology, Inc.	51,799	2,254,810
Teradyne, Inc.	79,734	7,140,180
Total		15,713,347
Software 14.3%
Avalara, Inc.^(a)	77,417	5,465,640
Bill.com Holdings, Inc.^(a)	65,053	7,151,927
Cadence Design Systems, Inc.^(a)	38,093	5,715,093
Crowdstrike Holdings, Inc., Class A^(a)	25,018	4,217,034
Five9, Inc.^(a)	65,448	5,964,931
HubSpot, Inc.^(a)	27,763	8,346,946
Paycom Software, Inc.^(a)	32,308	9,050,117
Trade Desk, Inc. (The), Class A^(a)	123,972	5,193,187
Workiva, Inc., Class A^(a)	65,205	4,302,878
Zscaler, Inc.^(a)	31,536	4,714,947
Total		60,122,700
Total Information Technology		101,214,479
Materials 2.6%
Chemicals 2.6%
Albemarle Corp.	30,318	6,335,857
Avient Corp.	117,202	4,697,456
Total		11,033,313
Total Materials		11,033,313
Real Estate 3.1%
Real Estate Management & Development 3.1%
Colliers International Group, Inc.	80,769	8,861,167
FirstService Corp.	32,670	3,959,604
Total		12,820,771
Total Real Estate		12,820,771
Total Common Stocks (Cost $454,762,946)		404,769,546

The accompanying Notes to Financial Statements are an integral part of this statement.

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Portfolio of Investments (continued)
June 30, 2022 (Unaudited)

Securities Lending Collateral 2.4%
Issuer	Shares	Value ($)
Dreyfus Government Cash Management Fund, Institutional Shares, 1.351%^(f),(g)	9,887,555	9,887,555
Total Securities Lending Collateral (Cost $9,887,555)		9,887,555

Money Market Funds 3.0%
	Shares	Value ($)
Columbia Short-Term Cash Fund, 1.247%^(f),(h)	12,789,598	12,781,924
Total Money Market Funds (Cost $12,780,817)		12,781,924
Total Investments in Securities (Cost: $477,431,318)		427,439,025
Obligation to Return Collateral for Securities Loaned		(9,887,555)
Other Assets & Liabilities, Net		2,924,563
Net Assets		420,476,033

Notes to Portfolio of Investments

(a)	Non-income producing investment.
(b)	All or a portion of this security was on loan at June 30, 2022. The total market value of securities on loan at June 30, 2022 was $9,112,706.
(c)	Represents fair value as determined in good faith under procedures approved by the Board of Trustees. At June 30, 2022, the total value of these securities amounted to $1,021,048, which represents 0.24% of total net assets.
(d)	Denotes a restricted security, which is subject to legal or contractual restrictions on resale under federal securities laws. Disposal of a restricted investment may involve time-consuming negotiations and expenses, and prompt sale at an acceptable price may be difficult to achieve. Private placement securities are generally considered to be restricted, although certain of those securities may be traded between qualified institutional investors under the provisions of Section 4(a)(2) and Rule 144A. The Fund will not incur any registration costs upon such a trade. These securities are valued at fair value determined in good faith under consistently applied procedures established by the Fund’s Board of Trustees. At June 30, 2022, the total market value of these securities amounted to $1,021,048, which represents 0.24% of total net assets. Additional information on these securities is as follows:

Security	Acquisition Dates	Shares	Cost ($)	Value ($)
DNA Script	10/01/2021	2,550	2,223,535	1,021,048

(e)	Valuation based on significant unobservable inputs.
(f)	The rate shown is the seven-day current annualized yield at June 30, 2022.
(g)	Investment made with cash collateral received from securities lending activity.
(h)	As defined in the Investment Company Act of 1940, as amended, an affiliated company is one in which the Fund owns 5% or more of the company’s outstanding voting securities, or a company which is under common ownership or control with the Fund. The value of the holdings and transactions in these affiliated companies during the period ended June 30, 2022 are as follows:

Affiliated issuers	Beginning of period($)	Purchases($)	Sales($)	Net change in unrealized appreciation (depreciation)($)	End of period($)	Realized gain (loss)($)	Dividends($)	End of period shares
Columbia Short-Term Cash Fund, 1.247%
	28,253,542	171,996,822	(187,470,794)	2,354	12,781,924	(5,970)	30,619	12,789,598

Abbreviation Legend

ADR	American Depositary Receipt

The accompanying Notes to Financial Statements are an integral part of this statement.

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Portfolio of Investments (continued)
June 30, 2022 (Unaudited)

Fair value measurements

■	Level 1 – quoted prices in active markets for identical securities

■	Level 2 – prices determined using other significant observable inputs (including quoted prices for similar securities, interest rates, prepayment speeds, credit risk and others)

■	Level 3 – prices determined using significant unobservable inputs where quoted prices or observable inputs are unavailable or less reliable (including management’s own assumptions about the factors market participants would use in pricing an investment)

The inputs or methodology used for valuing securities are not necessarily an indication of the risk associated with investing in those securities.

The following table is a summary of the inputs used to value the Fund’s investments at June 30, 2022:

	Level 1 ($)	Level 2 ($)	Level 3 ($)	Total ($)
Investments in Securities
Common Stocks
Communication Services	10,322,665	—	—	10,322,665
Consumer Discretionary	65,617,474	—	—	65,617,474
Consumer Staples	13,237,166	—	—	13,237,166
Energy	11,571,861	—	—	11,571,861
Financials	18,284,835	—	—	18,284,835
Health Care	80,284,343	—	1,021,048	81,305,391
Industrials	79,361,591	—	—	79,361,591
Information Technology	101,214,479	—	—	101,214,479
Materials	11,033,313	—	—	11,033,313
Real Estate	12,820,771	—	—	12,820,771
Total Common Stocks	403,748,498	—	1,021,048	404,769,546
Securities Lending Collateral	9,887,555	—	—	9,887,555
Money Market Funds	12,781,924	—	—	12,781,924
Total Investments in Securities	426,417,977	—	1,021,048	427,439,025

See the Portfolio of Investments for all investment classifications not indicated in the table.

The Fund does not hold any significant investments (greater than one percent of net assets) categorized as Level 3.

The accompanying Notes to Financial Statements are an integral part of this statement.

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Statement of Assets and Liabilities
June 30, 2022 (Unaudited)

Assets
Investments in securities, at value*
Unaffiliated issuers (cost $464,650,501)	$414,657,101
Affiliated issuers (cost $12,780,817)	12,781,924
Receivable for:
Investments sold	2,340,719
Capital shares sold	1,161,617
Dividends	70,014
Securities lending income	4,682
Foreign tax reclaims	4,246
Prepaid expenses	5,674
Total assets	431,025,977
Liabilities
Due upon return of securities on loan	9,887,555
Payable for:
Capital shares purchased	192,489
Investment advisory fee	8,606
Service fees	71,779
Administration fees	582
Trustees’ fees	307,002
Other expenses	81,931
Total liabilities	10,549,944
Net assets applicable to outstanding capital stock	$420,476,033
Represented by
Paid in capital	536,163,537
Total distributable earnings (loss)	(115,687,504)
Total - representing net assets applicable to outstanding capital stock	$420,476,033
Shares outstanding	40,134,603
Net asset value per share	10.48
* Includes the value of securities on loan	9,112,706

The accompanying Notes to Financial Statements are an integral part of this statement.

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Statement of Operations
Six Months Ended June 30, 2022 (Unaudited)

Net investment income
Income:
Dividends — unaffiliated issuers	$1,434,559
Dividends — affiliated issuers	30,619
Income from securities lending — net	75,926
Foreign taxes withheld	(3,837)
Total income	1,537,267
Expenses:
Investment advisory fee	2,171,720
Service fees	284,236
Administration fees	130,357
Trustees’ fees	30,700
Custodian fees	4,251
Printing and postage fees	78,614
Audit fees	14,841
Legal fees	43,616
Compensation of chief compliance officer	1,009
Other	23,400
Total expenses	2,782,744
Net investment loss	(1,245,477)
Realized and unrealized gain (loss) — net
Net realized gain (loss) on:
Investments — unaffiliated issuers	(62,582,743)
Investments — affiliated issuers	(5,970)
Foreign currency translations	(429)
Net realized loss	(62,589,142)
Net change in unrealized appreciation (depreciation) on:
Investments — unaffiliated issuers	(181,361,846)
Investments — affiliated issuers	2,354
Foreign currency translations	(1)
Net change in unrealized appreciation (depreciation)	(181,359,493)
Net realized and unrealized loss	(243,948,635)
Net decrease in net assets resulting from operations	$(245,194,112)

The accompanying Notes to Financial Statements are an integral part of this statement.

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Statement of Changes in Net Assets

	Six Months Ended June 30, 2022 (Unaudited)	Year Ended December 31, 2021
Operations
Net investment loss	$(1,245,477)	$(5,118,895)
Net realized gain (loss)	(62,589,142)	183,970,845
Net change in unrealized appreciation (depreciation)	(181,359,493)	(115,820,262)
Net increase (decrease) in net assets resulting from operations	(245,194,112)	63,031,688
Distributions to shareholders
Net investment income and net realized gains	(169,551,478)	(28,687,811)
Total distributions to shareholders	(169,551,478)	(28,687,811)
Increase (decrease) in net assets from capital stock activity	149,668,022	(57,132,932)
Total decrease in net assets	(265,077,568)	(22,789,055)
Net assets at beginning of period	685,553,601	708,342,656
Net assets at end of period	$420,476,033	$685,553,601

	Six Months Ended		Year Ended
	June 30, 2022 (Unaudited)		December 31, 2021
	Shares	Dollars ($)	Shares	Dollars ($)
Capital stock activity

Subscriptions	476,634	8,075,243	441,420	11,645,845
Distributions reinvested	14,516,394	169,551,478	1,127,646	28,687,811
Redemptions	(1,487,932)	(27,958,699)	(3,703,083)	(97,466,588)
Total net increase (decrease)	13,505,096	149,668,022	(2,134,017)	(57,132,932)

The accompanying Notes to Financial Statements are an integral part of this statement.

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Financial Highlights

	Six Months Ended June 30, 2022 (Unaudited)	Year Ended December 31,
	Six Months Ended June 30, 2022 (Unaudited)	2021	2020	2019	2018	2017
Per share data
Net asset value, beginning of period	$25.74	$24.63	$22.26	$20.70	$26.74	$26.53
Income from investment operations:
Net investment income (loss)	(0.04)	(0.19)	(0.12)	(0.02)	(0.02)	(0.02)
Net realized and unrealized gain (loss)	(8.63)	2.36	4.78	5.93	0.75	4.81
Total from investment operations	(8.67)	2.17	4.66	5.91	0.73	4.79
Less distributions to shareholders from:
Net investment income	—	(0.20)	—	(0.07)	(0.03)	—
Net realized gains	(6.59)	(0.86)	(2.29)	(4.28)	(6.74)	(4.58)
Total distributions to shareholders	(6.59)	(1.06)	(2.29)	(4.35)	(6.77)	(4.58)
Net asset value, end of period	$10.48	$25.74	$24.63	$22.26	$20.70	$26.74
Total return	(36.32%)	8.90%	24.23%	31.10%^(a)	(1.46%)^(a)	19.58%^(a)
Ratios to average net assets
Total gross expenses^(b)	1.07%^(c)	1.08%	1.10%	1.09%	1.05%	1.03%
Total net expenses^(b)	1.07%^(c)	1.08%	1.10%	1.06%	1.00%	0.99%
Net investment loss	(0.48)%^(c)	(0.71)%	(0.61)%	(0.08)%	(0.09)%	(0.08)%
Supplemental data
Portfolio turnover	81%	70%	92%	90%	81%	96%
Net assets, end of period (in thousands)	$420,476	$685,554	$708,343	$666,953	$581,991	$684,712

Notes to Financial Highlights
(a)	Had the Investment Manager and/or its affiliates not waived a portion of expenses, total return would have been reduced.
(b)	In addition to the fees and expenses that the Fund bears directly, the Fund indirectly bears a pro rata share of the fees and expenses of any other funds in which it invests. Such indirect expenses are not included in the Fund’s reported expense ratios.
(c)	Annualized.

The accompanying Notes to Financial Statements are an integral part of this statement.

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Notes to Financial Statements
June 30, 2022 (Unaudited)

Note 1. Organization

Wanger Acorn (formerly known as Wanger USA) (the Fund), a series of Wanger Advisors Trust (the Trust), is registered under the Investment Company Act of 1940, as amended (the 1940 Act), as an open-end management investment company organized as a Massachusetts business trust. The investment objective of the Fund is to seek long-term capital appreciation. The Fund is available only for allocation to certain life insurance company separate accounts established for the purpose of funding participating variable annuity contracts and variable life insurance policies and may also be offered directly to certain qualified pension and retirement plans.

Effective May 1, 2022, Wanger USA was renamed Wanger Acorn.

Note 2. Summary of significant accounting policies

Basis of preparation

The following is a summary of significant accounting policies followed by the Fund in the preparation of its financial statements.

Security valuation

Investments in open-end investment companies (other than exchange-traded funds (ETFs)), are valued at the latest net asset value reported by those companies as of the valuation time.

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Notes to Financial Statements (continued)
June 30, 2022 (Unaudited)

Fund share valuation

Foreign currency transactions and translations

Securities lending

The Fund may lend securities up to one-third of the value of its total assets to certain approved brokers, dealers, banks or other institutional borrowers of securities that the Fund’s securities lending agent has determined are credit worthy under guidelines established by the Board of Trustees, to earn additional income. The Fund retains the benefits of owning the securities, including the economic equivalent of dividends or interest generated by the security. The Fund also receives a fee for the loan. The Fund has the ability to recall the loans at any time and could do so in order to vote proxies or to sell the loaned securities. Each loan is collateralized by cash that exceeded the value of the securities on loan. The market value of the loaned securities is determined daily at the close of business of the Fund and any additional required collateral is delivered to the Fund on the next business day. The Fund typically invests the cash collateral in the Dreyfus Government Cash Management Fund, a third-party institutional government money market fund in accordance with investment guidelines contained in the securities lending agreement and approved by the Board of Trustees. The income earned from the securities lending program is paid to the Fund, net of any fees remitted to Goldman Sachs Agency Lending, the Fund’s lending agent, and borrower rebates. The Fund’s investment manager, Columbia Wanger Asset Management, LLC (the Investment Manager or CWAM), does not retain any fees earned by the lending program. Generally, in the event of borrower default, the Fund has the right to use the collateral to offset any losses incurred. In the event the Fund is delayed or prevented from exercising its right to dispose of the collateral, there may be a potential loss to the Fund. Some of these losses may be indemnified by the lending agent. The Fund bears the risk of loss with respect to the investment of collateral. The net lending income earned by the Fund as of June 30, 2022, is included in the Statement of Operations.

The following table indicates the total amount of securities loaned by type, reconciled to gross liability payable upon return of the securities loaned by the Fund as of June 30, 2022:

	Overnight and continuous	Up to 30 days	30-90 days	Greater than 90 days	Total
Wanger Acorn
Securities lending transactions
Equity securities	$9,112,706	$—	$—	$—	$9,112,706
Gross amount of recognized liabilities for securities lending (collateral received)					9,887,555
Amounts due to counterparty in the event of default					$774,849

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Notes to Financial Statements (continued)
June 30, 2022 (Unaudited)

Offsetting of assets and liabilities

The following table presents the Fund’s gross and net amount of assets and liabilities available for offset under netting arrangements as well as any related collateral received or pledged by the Fund as of June 30, 2022:

	Goldman Sachs ($)
Liabilities
Collateral on Securities Loaned	9,887,555
Total Liabilities	9,887,555
Total Financial and Derivative Net Assets	(9,887,555)
Financial Instruments	9,112,706
Net Amount ^(a)	(774,849)

(a)	Represents the net amount due from/(to) counterparties in the event of default.

Security transactions and investment income

Income recognition

Expenses

Federal income tax status

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Notes to Financial Statements (continued)
June 30, 2022 (Unaudited)

Foreign taxes

Distributions to shareholders

Distributions to shareholders are recorded on the ex-dividend date.

Guarantees and indemnification

Note 3. Fees and other transactions with affiliates

Management services fees

CWAM receives a monthly advisory fee based on the Fund’s daily net assets at the following annual rates:

Average daily net assets	Annual fee rate
Up to $700 million	0.74%
$700 million to $2 billion	0.69%
$2 billion to $6 billion	0.64%
$6 billion and over	0.63%

In February 2022, the Board approved a reduction in the advisory fee rates payable to the Investment Manager by the Fund. The new advisory fee, which became effective May 1, 2022, is included in the table above. Prior to May 1, 2022, the advisory fee was equal to a percentage of the Fund’s average daily net assets equal to 0.94% on the first $100 million, 0.89% from $100 million to $250 million, 0.84% from $250 million to $2 billion and 0.80% for $2 billion and over.

For the six months ended June 30, 2022, the annualized effective investment advisory fee rate was 0.83% of the Fund’s average daily net assets.

Administration fees

CWAM provides administrative services and receives an administration fee from the Fund at the following annual rates:

Aggregate average daily net assets of the Trust	Annual fee rate
Up to $4 billion	0.05%
$4 billion to $6 billion	0.04%
$6 billion to $8 billion	0.03%
$8 billion and over	0.02%

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Notes to Financial Statements (continued)
June 30, 2022 (Unaudited)

Compensation of board members

Compensation of Chief Compliance Officer

Service fees

Distributor

Columbia Management Investment Distributors, Inc., a wholly owned subsidiary of Ameriprise Financial, serves as the Fund’s distributor and principal underwriter.

Other expenses waived/reimbursed by the Investment Manager and its affiliates

Through April 30, 2023, CWAM has contractually agreed to bear a portion of the Fund’s expenses so that its ordinary operating expenses (excluding transaction costs and certain other investment-related expenses, interest and fees on borrowings and expenses associated with the Fund’s investment in other investment companies, if any), do not exceed the annual rate of 1.09% of the Fund’s average daily net assets. This agreement is an extension of the arrangement that was previously in place through April 30, 2022. It may not be modified or terminated, without approval from the Fund’s Board of Trustees and CWAM. There is no guarantee that this agreement will continue after April 30, 2023.

Note 4. Federal tax information

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Notes to Financial Statements (continued)
June 30, 2022 (Unaudited)

At June 30, 2022, the approximate cost of all investments for federal income tax purposes and the aggregate gross approximate unrealized appreciation and depreciation based on that cost was:

Federal tax cost ($)	Gross unrealized appreciation ($)	Gross unrealized (depreciation) ($)	Net unrealized (depreciation) ($)
477,431,000	43,373,000	(93,365,000)	(49,992,000)

Tax cost of investments and unrealized appreciation/(depreciation) may also include timing differences that do not constitute adjustments to tax basis.

Note 5. Portfolio information

The aggregate cost of purchases and proceeds from sales other than short-term obligations for the six months ended June 30, 2022, were $418,291,517 and $426,886,606, respectively. The amount of purchase and sales activity impacts the portfolio turnover rate reported in the Financial Highlights.

Note 6. Affiliated money market fund

Note 7. Line of credit

The Fund had no borrowings during the six months ended June 30, 2022.

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Notes to Financial Statements (continued)
June 30, 2022 (Unaudited)

Note 8. Significant risks

Information technology sector risk

Market risk

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Notes to Financial Statements (continued)
June 30, 2022 (Unaudited)

political, social and economic risks in certain countries or globally. The disruptions caused by COVID-19 could prevent the Fund from executing advantageous investment decisions in a timely manner and negatively impact the Fund’s ability to achieve its investment objective. Any such events could have a significant adverse impact on the value and risk profile of the Fund.

Shareholder concentration risk

At June 30, 2022, two unaffiliated shareholders of record owned 33.8% of the outstanding shares of the Fund in one or more accounts. The Fund has no knowledge about whether any portion of those shares was owned beneficially. Affiliated shareholders of record owned 59.2% of the outstanding shares of the Fund in one or more accounts. Subscription and redemption activity by concentrated accounts may have a significant effect on the operations of the Fund. In the case of a large redemption, the Fund may be forced to sell investments at inopportune times, including its liquid positions, which may result in Fund losses and the Fund holding a higher percentage of less liquid positions. Large redemptions could result in decreased economies of scale and increased operating expenses for non-redeeming Fund shareholders.

Small- and mid-cap company risk

Note 9. Subsequent events

Note 10. Information regarding pending and settled legal proceedings

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Liquidity Risk Management Program

(Unaudited)

•	the Fund had sufficient liquidity to both meet redemptions and operate effectively on behalf of shareholders;
•	there were no material changes to the Program during the period;
•	the Fund’s strategy continued to be effective for an open-end mutual fund;
•	the implementation of the Program was effective to manage the Fund’s liquidity risk;
•	the Fund did not require a highly liquid investment minimum; and
•	the Program operated adequately during the period.

Board Consideration and Approval of Advisory

Agreement

(Unaudited)

Wanger Advisors Trust (the “Trust”) has an investment advisory agreement (the “Advisory Agreement”) with Columbia Wanger Asset Management, LLC (“CWAM”) under which CWAM manages Wanger Acorn (formerly known as Wanger USA) (the “Fund”). All of the voting trustees of the Trust are persons who have no direct or indirect interest in the Advisory Agreement and are not “interested persons” (as defined in the Investment Company Act of 1940, as amended (the “1940 Act”)) of the Trust (the “Independent Trustees”). The Independent Trustees oversee the management of the Fund and, as required by law, determine at least annually whether to continue the Advisory Agreement for the Fund.

22	Wanger Acorn \| Semiannual Report 2022

Table of Contents

Board Consideration and Approval of Advisory

Agreement (continued)

(Unaudited)

The materials reviewed by the Contract Committee and the Independent Trustees included, among other items: (i) information on the investment performance of the Fund relative to independently selected peer groups of funds and the Fund’s performance benchmark over various time periods, as presented and analyzed by an independent consultant; (ii) information on the Fund’s advisory fees and other expenses, including information comparing the Fund’s fees and expenses to those of a peer group of funds and information about any applicable expense limitations and fee breakpoints; (iii) data on sales and redemptions of Fund shares; and (iv) information on the profitability to CWAM and its affiliates, as well as potential “fall-out” or ancillary benefits that CWAM and its affiliates may receive as a result of their relationships with the Fund. The Contract Committee and the Board also considered other information, such as: (i) CWAM’s financial condition; (ii) the Fund’s investment objective and strategy; (iii) the overall level of resources devoted to the Fund; (iv) the size, education, experience and resources of CWAM’s investment staff and its use of technology, including with respect to the liquidity risk management program and external research and trading cost measurement tools; (v) changes in investment and other personnel at CWAM; (vi) the portfolio manager compensation framework at CWAM; (vii) the allocation of the Fund’s brokerage, and the use of “soft” commission dollars to pay for research products and services; (viii) CWAM’s risk management program; (ix) the resources devoted to, and the record of compliance with, the Fund’s investment policies and restrictions, policies on personal securities transactions and other compliance policies and procedures; (x) CWAM’s and its affiliates’ conflicts of interest; and (xi) CWAM’s management of the Fund in light of market and operating conditions arising from the COVID-19 pandemic.

Nature, quality and extent of services

The Independent Trustees reviewed the nature, quality and extent of the services provided by CWAM and its affiliates to the Fund under the Advisory Agreement, taking into account the investment objective and strategy of the Fund, its shareholder base and knowledge gained from meetings with management, which were held on at least a quarterly basis. They reviewed the available resources and key personnel of CWAM and its affiliates, especially those providing investment management services to the Fund. They also considered the resources dedicated specifically to CWAM by its parent company pursuant to the Advisory Agreement and the contribution of those resources to the portfolio management process. The Independent Trustees also took into account other services provided to the Fund by CWAM and its affiliates, including: managing the execution of portfolio transactions and selecting broker-dealers for those transactions; monitoring adherence to the Fund’s investment restrictions; monitoring and managing the Fund’s liquidity pursuant to the liquidity risk management program; providing support services for, and regular updates on the operations of the Fund to, the Board and committees of the Board; managing the Fund’s securities lending program; communicating with shareholders; serving as the Fund’s administrator and fund accountant; and overseeing the activities of the Fund’s other service providers, including monitoring for compliance with

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Table of Contents

Board Consideration and Approval of Advisory

Agreement (continued)

(Unaudited)

various policies and procedures as well as applicable securities laws and regulations. The Independent Trustees also considered CWAM’s ability to operate from a remote working environment in connection with the COVID-19 pandemic without any adverse impact on the Fund or shareholders. The Independent Trustees also noted the quality of CWAM’s compliance record.

The Independent Trustees considered that, based upon the recommendation of CWAM and Columbia Management, effective May 1, 2022, (i) the Fund’s name was changed, the market capitalization range of the companies in which the Fund invests a majority of its assets was increased, the limit on the Fund’s foreign investments was increased and its primary benchmark was changed to align with the investment strategies, investment policies and primary benchmark of Columbia Acorn Fund, a series of Columbia Acorn Trust managed by CWAM, (ii) CWAM’s Domestic Team Head became a portfolio manager of the Fund and (iii) the Fund’s advisory fee schedule was permanently reduced to align with that of Columbia Acorn Fund. The Independent Trustees noted that a principal aim of CWAM and Columbia Management in implementing the changes was to improve long-term investment outcomes for shareholders of the Fund. The Independent Trustees also considered CWAM’s extensive and focused efforts to continue to improve the performance of the Fund and believed they were reasonable and appropriate.

Performance of the Fund

The Independent Trustees received and considered information comparing the Fund’s performance with that of comparable funds and peer groups as identified by independent consultant Broadridge Financial Solutions, Inc. (“Broadridge”) and the performance of the Fund’s primary benchmark. The Independent Trustees evaluated the performance and risk characteristics of the Fund over various periods, including over the one-, three- and five-year periods ended December 31, 2021, and April 30, 2022. They considered that the Fund had outperformed its Broadridge peer group median for the one-year period ended December 31,2021, and underperformed its Broadridge peer group median for the three- and five-year periods ended December 31, 2021. They also took into account that the Fund had outperformed its former (prior to May 1, 2022) primary benchmark, the Russell 2000 Growth Index, for the one- and five-year periods ended December 31, 2021, and underperformed the Russell 2000 Growth Index, for the three-year period ended December 31, 2021. In addition, the Independent Trustees considered that the Fund had underperformed its Broadridge peer group median and the Russell 2000 Growth Index for the one-, three- and five-year periods ended April 30, 2022.

The Independent Trustees concluded that CWAM had taken, and continued to take, a number of corrective steps to improve the Fund’s performance and that the Performance Committee was monitoring the Fund’s performance closely. In addition, the Independent Trustees considered that CWAM’s Domestic Team Head and Director of Research (U.S.) had reported to them at numerous Contract Committee, Performance Committee and Board meetings on the corrective steps taken over the past several years to improve the Fund’s performance.

Costs of services and profits realized by CWAM

The Independent Trustees examined detailed information on the fees and expenses of the Fund compared with information for similar funds provided by Broadridge.

They considered that, although the Fund’s net expenses and actual advisory fees paid were higher than the median of its Broadridge peer group, CWAM had contractually agreed to permanently reduce the Fund’s advisory fee schedule effective May 1, 2022. The Independent Trustees also took into account that, effective May 1, 2022, Wanger Acorn and Wanger Select, another series of the Trust, as well as their Columbia Acorn Trust counterparts, Columbia Acorn Fund and Columbia Acorn USA, (together, the “Domestic Funds”), were managed in an identical manner by the same portfolio managers and that

24	Wanger Acorn \| Semiannual Report 2022

Table of Contents

Board Consideration and Approval of Advisory

Agreement (continued)

(Unaudited)

the advisory fee schedule for each of the Domestic Funds was identical. The Independent Trustees also considered that CWAM had contractually agreed through April 30, 2023, to extend the existing contractual limit on the Fund’s fees and expenses such that the Fund would experience a net decrease in total operating expenses of 0.14% from the prior year. In addition, the Independent Trustees reviewed information prepared by Broadridge with respect to the total expenses of the Fund relative to its three- and five-year performance.

The Independent Trustees took into account that, although CWAM did not manage other investment companies as a sub-adviser or other institutional separate accounts that had investment strategies similar to the Fund, Columbia Management and the Fund’s portfolio managers provided investment advisory services to a collective investment trust with a single investor (the “CIT”) that followed an investment strategy substantially similar to that of the Domestic Funds and paid higher advisory fees than the effective advisory fee rates paid by the Domestic Funds. They considered that Columbia Management might in the future reduce the CIT advisory fee below that paid by the Domestic Funds. The Independent Trustees also considered information provided by CWAM regarding its performance of significant additional services for the Fund that Columbia Management did not provide to non-mutual fund clients, such as the CIT, including certain administrative services, oversight of the Fund’s other service providers, Independent Trustee support, regulatory compliance and numerous other services, and that, in servicing the Fund, CWAM assumed many legal and business risks that Columbia Management did not assume in servicing non-fund clients.

The Independent Trustees reviewed the analysis of CWAM’s profitability in serving as the Fund’s investment manager and of CWAM and its affiliates in their relationships with the Fund. They considered that the Contract Committee and the Board met with representatives from Ameriprise to discuss its methodologies for calculating profitability and allocating costs. They considered that Ameriprise calculated profitability and allocated costs on a contract-by-contract and fund-by-fund basis. In addition, the Independent Trustees considered an analysis of CWAM’s anticipated profitability in serving as investment manager to the funds in the Trust and Columbia Acorn Trust at various hypothetical levels of total assets. They also reviewed the methodology used by CWAM and Ameriprise to determine the level of compensation payable to portfolio managers and the competitive market for investment management talent and whether the methodology was aligned with shareholders’ interests. The Independent Trustees were provided with profitability information from a third-party consultant, Strategic Insight, which compared CWAM’s profitability to other similar investment managers in the mutual fund industry. The Independent Trustees discussed, however, that profitability comparisons among fund managers may not always be meaningful due to the lack of consistency in data, small number of publicly-owned managers, and the fact that the profitability of any investment manager is affected by numerous factors, including its particular organizational structure, the types of funds and other accounts managed, other lines of business, expense allocation methodology, capital structure and other factors. The Independent Trustees evaluated CWAM’s profitability in light of the additional resources that had been, and would continue to be, provided to the Fund by Ameriprise to assist in improving Fund performance.

Economies of scale

At various Committee and Board meetings and other informal meetings, the Independent Trustees also considered information about the extent to which CWAM realized economies of scale in connection with an increase in Fund assets. It was noted, however, that the Fund had lost assets over the past several years. The Independent Trustees considered that the advisory fee schedule for the Fund included breakpoints in the rate of fees at various asset levels. In evaluating whether CWAM was sharing economies of scale with Fund shareholders, the Independent Trustees also took into account the expense limitation that CWAM had agreed to implement for the Fund for 2022 and 2023 and CWAM’s contractual agreement to permanently reduce its advisory fee for the Fund effective May 1, 2022. The Independent Trustees concluded that the fee structure of the Advisory Agreement for the Fund reflected a sharing of economies of scale between CWAM and the Fund.

Other benefits to CWAM

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Table of Contents

Board Consideration and Approval of Advisory

Agreement (continued)

(Unaudited)

Investment Distributors, Inc., served as the Fund’s distributor under an underwriting agreement but received no fees for its services to the Fund. In addition, they considered that Columbia Management provided sub-administration services to the Fund. The Contract Committee and the Board received information regarding the profitability of these Fund agreements to the CWAM affiliates and also reviewed information about and discussed the capabilities of each affiliated entity in performing its respective duties.

26	Wanger Acorn \| Semiannual Report 2022

Table of Contents

Fund at a Glance	3
Understanding Your Fund’s Expenses	5
Portfolio of Investments	6
Statement of Assets and Liabilities	10
Statement of Operations	11
Statement of Changes in Net Assets	12
Financial Highlights	13
Notes to Financial Statements	14
Liquidity Risk Management Program	23
Board Consideration and Approval of Advisory Agreement	23

Proxy voting policies and procedures

The policy of the Board of Trustees is to vote the proxies of the companies in which Wanger Select (the Fund) holds investments consistent with the procedures as stated in the Statement of Additional Information (SAI). You may obtain a copy of the SAI without charge by calling 800.345.6611; contacting your financial intermediary; visiting columbiathreadneedleus.com/investor/; or searching the website of the Securities and Exchange Commission (SEC) at sec.gov. Information regarding how the Fund voted proxies relating to portfolio securities is filed with the SEC by August 31st for the most recent 12-month period ending June 30th of that year, and is available without charge by visiting columbiathreadneedleus.com/investor/, or searching the website of the SEC at sec.gov.

Quarterly schedule of investments

Additional Fund information

Fund investment manager

Columbia Wanger Asset Management, LLC (the Investment Manager)

71 S Wacker Drive, Suite 2500

Chicago, IL 60606

888.4.WANGER

(888.492.6437)

Fund distributor

Columbia Management Investment Distributors, Inc.

290 Congress Street

Boston, MA 02210

Fund transfer agent

Columbia Management Investment Services Corp.

P.O. Box 219104

Kansas City, MO 64121-9104

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Table of Contents

Fund at a Glance
(Unaudited)

Investment objective

The Fund seeks long-term capital appreciation.

Portfolio management

Daniel Cole, CFA

Co-Portfolio Manager since 2021

Service with Fund since 2021

Erika K. Maschmeyer, CFA

Co-Portfolio Manager since 2021

Service with Fund since 2016

John L. Emerson, CFA

Co-Portfolio Manager since 2019

Service with Fund since 2003

Average annual total returns (%) (for the period ended June 30, 2022)
	Inception	6 Months cumulative	1 Year	5 Years	10 Years	Life of Fund
Wanger Select	02/01/99	-37.77	-39.92	1.37	7.49	8.39
Russell 2500 Growth Index		-29.45	-31.81	7.53	10.88	-

The Fund’s annual operating expense ratio of 0.95% is stated in the Fund’s prospectus dated May 1, 2022, and differences in expense ratios disclosed elsewhere in this report may result from the reflection of fee waivers and/or expense reimbursements as well as different time periods used in calculating the ratios.

All results shown assume reinvestment of distributions.

The Russell 2500 Growth Index measures the performance of those Russell 2500 companies with higher price-to-book ratios and higher forecasted growth values.

The Fund’s performance prior to May 1, 2022 reflects returns achieved pursuant to a strategy that included investing in a limited number of companies (generally 20-40). If the Fund’s current strategies had been in place for the prior periods, results shown would have been different.

Indexes are not managed and do not incur fees or expenses. It is not possible to invest directly in an index.

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Table of Contents

Understanding Your Fund’s Expenses
(Unaudited)

As a shareholder, you incur three types of costs. There are shareholder transaction costs, which may include redemption fees. There are also ongoing fund costs, which generally include investment advisory fees and other expenses for Wanger Select (the Fund). Lastly, there may be additional fees or charges imposed by the insurance company that sponsors your variable annuity and/or variable life insurance product. The following information is intended to help you understand your ongoing costs (in dollars) of investing in the Fund and to help you compare these costs with the ongoing costs of investing in other mutual funds.

Analyzing your Fund’s expenses

Compare with other funds

January 1, 2022 — June 30, 2022
	Account value at the beginning of the period ($)		Account value at the end of the period ($)		Expenses paid during the period ($)		Fund’s annualized expense ratio (%)
	Actual	Hypothetical	Actual	Hypothetical	Actual	Hypothetical	Actual
Wanger Select	1,000.00	1,000.00	622.30	1,020.28	3.66	4.56	0.91

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Portfolio of Investments
June 30, 2022 (Unaudited)

(Percentages represent value of investments compared to net assets)

Investments in securities

Common Stocks 96.4%
Issuer	Shares	Value ($)
Communication Services 2.5%
Entertainment 2.5%
Roblox Corp., Class A^(a)	12,001	394,353
Take-Two Interactive Software, Inc.^(a)	10,209	1,250,909
Total		1,645,262
Total Communication Services		1,645,262
Consumer Discretionary 15.7%
Auto Components 1.2%
Dorman Products, Inc.^(a)	7,293	800,115
Diversified Consumer Services 2.3%
Bright Horizons Family Solutions, Inc.^(a)	7,973	673,878
Chegg, Inc.^(a)	44,636	838,264
Total		1,512,142
Hotels, Restaurants & Leisure 5.9%
Churchill Downs, Inc.	5,647	1,081,570
Planet Fitness, Inc., Class A^(a)	20,937	1,423,925
Wingstop, Inc.	19,265	1,440,444
Total		3,945,939
Household Durables 2.1%
Skyline Champion Corp.^(a)	30,005	1,422,837
Internet & Direct Marketing Retail 0.8%
Etsy, Inc.^(a)	7,230	529,308
Specialty Retail 3.4%
Five Below, Inc.^(a)	9,510	1,078,719
Floor & Decor Holdings, Inc.^(a)	6,935	436,628
Williams-Sonoma, Inc.	6,568	728,720
Total		2,244,067
Total Consumer Discretionary		10,454,408
Consumer Staples 3.2%
Food & Staples Retailing 1.4%
BJ’s Wholesale Club Holdings, Inc.^(a)	15,255	950,692
Household Products 1.8%
WD-40 Co.	5,757	1,159,229
Total Consumer Staples		2,109,921

Common Stocks (continued)
Issuer	Shares	Value ($)
Energy 2.8%
Oil, Gas & Consumable Fuels 2.8%
Antero Resources Corp.^(a)	8,717	267,176
Devon Energy Corp.	14,547	801,685
Diamondback Energy, Inc.	6,390	774,149
Total		1,843,010
Total Energy		1,843,010
Financials 4.3%
Banks 1.1%
Lakeland Financial Corp.	11,385	756,191
Capital Markets 2.7%
Ares Management Corp., Class A	12,982	738,157
GCM Grosvenor, Inc., Class A	80,824	553,644
Houlihan Lokey, Inc., Class A	6,958	549,195
Total		1,840,996
Insurance 0.5%
Ryan Specialty Holdings, Inc., Class A^(a)	7,968	312,266
Total Financials		2,909,453
Health Care 19.2%
Biotechnology 3.3%
Argenx SE, ADR^(a)	1,357	514,140
Insmed, Inc.^(a)	20,961	413,351
Intellia Therapeutics, Inc.^(a)	4,553	235,663
Iovance Biotherapeutics, Inc.^(a)	16,188	178,716
Natera, Inc.^(a)	23,550	834,612
Total		2,176,482
Health Care Equipment & Supplies 2.8%
Axonics, Inc.^(a)	10,030	568,400
Insulet Corp.^(a)	6,042	1,316,793
Total		1,885,193
Health Care Providers & Services 4.1%
Amedisys, Inc.^(a)	9,862	1,036,693
Chemed Corp.	3,115	1,462,150
P3 Health Partners, Inc., Class A^(a),(b)	62,196	231,369
Total		2,730,212

The accompanying Notes to Financial Statements are an integral part of this statement.

6	Wanger Select \| Semiannual Report 2022

Table of Contents

Portfolio of Investments (continued)
June 30, 2022 (Unaudited)

Common Stocks (continued)
Issuer	Shares	Value ($)
Health Care Technology 2.1%
Doximity, Inc., Class A^(a),(b)	29,206	1,016,953
Inspire Medical Systems, Inc.^(a)	2,046	373,743
Total		1,390,696
Life Sciences Tools & Services 5.1%
Bio-Techne Corp.	5,091	1,764,744
Repligen Corp.^(a)	9,989	1,622,214
Total		3,386,958
Pharmaceuticals 1.8%
Catalent, Inc.^(a)	11,307	1,213,128
Total Health Care		12,782,669
Industrials 18.9%
Commercial Services & Supplies 1.7%
Rollins, Inc.	32,844	1,146,913
Electrical Equipment 4.1%
AMETEK, Inc.	11,670	1,282,416
Atkore, Inc.^(a)	6,411	532,177
Generac Holdings, Inc.^(a)	4,410	928,658
Total		2,743,251
Machinery 5.8%
Ingersoll Rand, Inc.	27,161	1,142,935
Kornit Digital Ltd.^(a)	16,125	511,163
Middleby Corp. (The)^(a)	6,726	843,171
SPX Corp.^(a)	26,454	1,397,829
Total		3,895,098
Professional Services 5.2%
Booz Allen Hamilton Holdings Corp.	12,105	1,093,808
CoStar Group, Inc.^(a)	26,006	1,571,022
ICF International, Inc.	8,210	779,950
Total		3,444,780
Trading Companies & Distributors 2.1%
SiteOne Landscape Supply, Inc.^(a)	11,856	1,409,323
Total Industrials		12,639,365
Information Technology 24.2%
Electronic Equipment, Instruments & Components 2.0%
CDW Corp.	8,645	1,362,106

Common Stocks (continued)
Issuer	Shares	Value ($)
IT Services 4.0%
DigitalOcean Holdings, Inc.^(a),(b)	12,543	518,778
Endava PLC, ADR^(a)	5,662	499,785
MongoDB, Inc.^(a)	3,735	969,233
VeriSign, Inc.^(a)	4,124	690,069
Total		2,677,865
Semiconductors & Semiconductor Equipment 3.8%
Enphase Energy, Inc.^(a)	5,162	1,007,829
Marvell Technology, Inc.	8,243	358,817
Teradyne, Inc.	12,709	1,138,091
Total		2,504,737
Software 14.4%
Avalara, Inc.^(a)	12,340	871,204
Bill.com Holdings, Inc.^(a)	10,362	1,139,198
Cadence Design Systems, Inc.^(a)	6,072	910,982
Crowdstrike Holdings, Inc., Class A^(a)	3,981	671,037
Five9, Inc.^(a)	10,432	950,773
HubSpot, Inc.^(a)	4,421	1,329,174
Paycom Software, Inc.^(a)	5,136	1,438,696
Trade Desk, Inc. (The), Class A^(a)	19,747	827,202
Workiva, Inc., Class A^(a)	10,393	685,834
Zscaler, Inc.^(a)	5,027	751,587
Total		9,575,687
Total Information Technology		16,120,395
Materials 2.6%
Chemicals 2.6%
Albemarle Corp.	4,832	1,009,792
Avient Corp.	18,681	748,735
Total		1,758,527
Total Materials		1,758,527
Real Estate 3.0%
Real Estate Management & Development 3.0%
Colliers International Group, Inc.	12,851	1,409,883
FirstService Corp.	5,207	631,089
Total		2,040,972
Total Real Estate		2,040,972
Total Common Stocks (Cost $81,626,897)		64,303,982

The accompanying Notes to Financial Statements are an integral part of this statement.

Wanger Select | Semiannual Report 2022

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Portfolio of Investments (continued)
June 30, 2022 (Unaudited)

Securities Lending Collateral 2.6%
Issuer	Shares	Value ($)
Dreyfus Government Cash Management Fund, Institutional Shares, 1.351%^(c),(d)	1,713,875	1,713,875
Total Securities Lending Collateral (Cost $1,713,875)		1,713,875

Money Market Funds 3.1%
	Shares	Value ($)
Columbia Short-Term Cash Fund, 1.247%^(c),(e)	2,075,060	2,073,815
Total Money Market Funds (Cost $2,073,664)		2,073,815
Total Investments in Securities (Cost: $85,414,436)		68,091,672
Obligation to Return Collateral for Securities Loaned		(1,713,875)
Other Assets & Liabilities, Net		290,148
Net Assets		66,667,945

Notes to Portfolio of Investments

(a)	Non-income producing investment.
(b)	All or a portion of this security was on loan at June 30, 2022. The total market value of securities on loan at June 30, 2022 was $1,583,464.
(c)	The rate shown is the seven-day current annualized yield at June 30, 2022.
(d)	Investment made with cash collateral received from securities lending activity.
(e)	As defined in the Investment Company Act of 1940, as amended, an affiliated company is one in which the Fund owns 5% or more of the company’s outstanding voting securities, or a company which is under common ownership or control with the Fund. The value of the holdings and transactions in these affiliated companies during the period ended June 30, 2022 are as follows:

Affiliated issuers	Beginning of period($)	Purchases($)	Sales($)	Net change in unrealized appreciation (depreciation)($)	End of period($)	Realized gain (loss)($)	Dividends($)	End of period shares
Columbia Short-Term Cash Fund, 1.247%
	1,120,250	22,492,104	(21,538,690)	151	2,073,815	(1,074)	5,278	2,075,060

Abbreviation Legend

ADR	American Depositary Receipt

Fair value measurements

■	Level 1 – quoted prices in active markets for identical securities

■	Level 2 – prices determined using other significant observable inputs (including quoted prices for similar securities, interest rates, prepayment speeds, credit risk and others)

■	Level 3 – prices determined using significant unobservable inputs where quoted prices or observable inputs are unavailable or less reliable (including management’s own assumptions about the factors market participants would use in pricing an investment)

The inputs or methodology used for valuing securities are not necessarily an indication of the risk associated with investing in those securities.

The accompanying Notes to Financial Statements are an integral part of this statement.

8	Wanger Select \| Semiannual Report 2022

Table of Contents

Portfolio of Investments (continued)
June 30, 2022 (Unaudited)

Fair value measurements (continued)
The Committee is responsible for applying the Wanger Advisors Trust Portfolio Pricing Policy and the Investment Manager’s pricing procedures (the Policies), which are approved by and subject to the oversight of the Board of Trustees.

The following table is a summary of the inputs used to value the Fund’s investments at June 30, 2022:

	Level 1 ($)	Level 2 ($)	Level 3 ($)	Total ($)
Investments in Securities
Common Stocks
Communication Services	1,645,262	—	—	1,645,262
Consumer Discretionary	10,454,408	—	—	10,454,408
Consumer Staples	2,109,921	—	—	2,109,921
Energy	1,843,010	—	—	1,843,010
Financials	2,909,453	—	—	2,909,453
Health Care	12,782,669	—	—	12,782,669
Industrials	12,639,365	—	—	12,639,365
Information Technology	16,120,395	—	—	16,120,395
Materials	1,758,527	—	—	1,758,527
Real Estate	2,040,972	—	—	2,040,972
Total Common Stocks	64,303,982	—	—	64,303,982
Securities Lending Collateral	1,713,875	—	—	1,713,875
Money Market Funds	2,073,815	—	—	2,073,815
Total Investments in Securities	68,091,672	—	—	68,091,672

See the Portfolio of Investments for all investment classifications not indicated in the table.

The accompanying Notes to Financial Statements are an integral part of this statement.

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Table of Contents

Statement of Assets and Liabilities
June 30, 2022 (Unaudited)

Assets
Investments in securities, at value*
Unaffiliated issuers (cost $83,340,772)	$66,017,857
Affiliated issuers (cost $2,073,664)	2,073,815
Receivable for:
Investments sold	374,574
Capital shares sold	83,031
Dividends	11,262
Securities lending income	1,575
Foreign tax reclaims	298
Expense reimbursement due from Investment Manager	344
Prepaid expenses	949
Total assets	68,563,705
Liabilities
Due upon return of securities on loan	1,713,875
Payable for:
Capital shares purchased	30,678
Investment advisory fee	1,367
Service fees	28,361
Administration fees	92
Trustees’ fees	73,655
Other expenses	47,732
Total liabilities	1,895,760
Net assets applicable to outstanding capital stock	$66,667,945
Represented by
Paid in capital	106,356,723
Total distributable earnings (loss)	(39,688,778)
Total - representing net assets applicable to outstanding capital stock	$66,667,945
Shares outstanding	11,246,606
Net asset value per share	5.93
* Includes the value of securities on loan	1,583,464

The accompanying Notes to Financial Statements are an integral part of this statement.

10	Wanger Select \| Semiannual Report 2022

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Statement of Operations
Six Months Ended June 30, 2022 (Unaudited)

Net investment income
Income:
Dividends — unaffiliated issuers	$213,392
Dividends — affiliated issuers	5,278
Income from securities lending — net	4,632
Foreign taxes withheld	(447)
Total income	222,855
Expenses:
Investment advisory fee	323,654
Service fees	74,180
Administration fees	20,677
Trustees’ fees	(7,801)
Custodian fees	1,878
Printing and postage fees	16,632
Audit fees	14,841
Legal fees	6,946
Compensation of chief compliance officer	163
Other	7,837
Total expenses	459,007
Fees waived or expenses reimbursed by Investment Manager and its affiliates	(24,991)
Advisory fee waiver	(58,801)
Total net expenses	375,215
Net investment loss	(152,360)
Realized and unrealized gain (loss) — net
Net realized gain (loss) on:
Investments — unaffiliated issuers	(21,879,426)
Investments — affiliated issuers	(1,074)
Foreign currency translations	143
Net realized loss	(21,880,357)
Net change in unrealized appreciation (depreciation) on:
Investments — unaffiliated issuers	(19,695,508)
Investments — affiliated issuers	151
Net change in unrealized appreciation (depreciation)	(19,695,357)
Net realized and unrealized loss	(41,575,714)
Net decrease in net assets resulting from operations	$(41,728,074)

The accompanying Notes to Financial Statements are an integral part of this statement.

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Statement of Changes in Net Assets

	Six Months Ended June 30, 2022 (Unaudited)	Year Ended December 31, 2021
Operations
Net investment loss	$(152,360)	$(917,233)
Net realized gain (loss)	(21,880,357)	38,519,405
Net change in unrealized appreciation (depreciation)	(19,695,357)	(30,168,545)
Net increase (decrease) in net assets resulting from operations	(41,728,074)	7,433,627
Distributions to shareholders
Net investment income and net realized gains	(37,838,106)	(13,070,321)
Total distributions to shareholders	(37,838,106)	(13,070,321)
Increase (decrease) in net assets from capital stock activity	33,197,466	(2,978,008)
Total decrease in net assets	(46,368,714)	(8,614,702)
Net assets at beginning of period	113,036,659	121,651,361
Net assets at end of period	$66,667,945	$113,036,659

	Six Months Ended		Year Ended
	June 30, 2022 (Unaudited)		December 31, 2021
	Shares	Dollars ($)	Shares	Dollars ($)
Capital stock activity

Subscriptions	141,478	1,833,470	92,636	1,902,600
Distributions reinvested	5,724,373	37,838,106	679,684	13,070,321
Redemptions	(474,678)	(6,474,110)	(875,762)	(17,950,929)
Total net increase (decrease)	5,391,173	33,197,466	(103,442)	(2,978,008)

The accompanying Notes to Financial Statements are an integral part of this statement.

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Financial Highlights

	Six Months Ended June 30, 2022 (Unaudited)	Year Ended December 31,
	Six Months Ended June 30, 2022 (Unaudited)	2021	2020	2019	2018	2017
Per share data
Net asset value, beginning of period	$19.30	$20.42	$18.29	$16.32	$20.84	$19.10
Income from investment operations:
Net investment income (loss)	(0.02)	(0.15)	(0.09)	(0.02)	0.07	0.04
Net realized and unrealized gain (loss)	(6.57)	1.33	4.44	4.48	(2.15)	4.62
Total from investment operations	(6.59)	1.18	4.35	4.46	(2.08)	4.66
Less distributions to shareholders from:
Net investment income	—	—	(0.14)	(0.02)	(0.04)	(0.03)
Net realized gains	(6.78)	(2.30)	(2.08)	(2.47)	(2.40)	(2.89)
Total distributions to shareholders	(6.78)	(2.30)	(2.22)	(2.49)	(2.44)	(2.92)
Net asset value, end of period	$5.93	$19.30	$20.42	$18.29	$16.32	$20.84
Total return^(a)	(37.77%)	5.83%	26.65%	29.30%	(12.41%)	26.67%
Ratios to average net assets
Total gross expenses^(b)	1.11%^(c)	1.15%	1.16%^(d)	1.15%	1.10%	1.05%
Total net expenses^(b)	0.91%^(c)	0.89%	0.89%^(d)	0.88%	0.78%	0.77%
Net investment income (loss)	(0.37)%^(c)	(0.75)%	(0.54)%	(0.14)%	0.34%	0.19%
Supplemental data
Portfolio turnover	67%	119%	109%	152%	66%	52%
Net assets, end of period (in thousands)	$66,668	$113,037	$121,651	$116,679	$106,469	$141,213

Notes to Financial Highlights
(a)	Had the Investment Manager and/or its affiliates not waived a portion of expenses, total return would have been reduced.
(b)	In addition to the fees and expenses that the Fund bears directly, the Fund indirectly bears a pro rata share of the fees and expenses of any other funds in which it invests, if any. Such indirect expenses are not included in the Fund’s reported expense ratios.
(c)	Annualized.
(d)	Ratios include line of credit interest expense which is less than 0.01%.

The accompanying Notes to Financial Statements are an integral part of this statement.

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Notes to Financial Statements
June 30, 2022 (Unaudited)

Note 1. Organization

Wanger Select (the Fund), a series of Wanger Advisors Trust (the Trust), is registered under the Investment Company Act of 1940, as amended (the 1940 Act), as an open-end management investment company organized as a Massachusetts business trust. The investment objective of the Fund is to seek long-term capital appreciation. The Fund is available only for allocation to certain life insurance company separate accounts established for the purpose of funding participating variable annuity contracts and variable life insurance policies and may also be offered directly to certain qualified pension and retirement plans.

Note 2. Summary of significant accounting policies

Basis of preparation

The following is a summary of significant accounting policies followed by the Fund in the preparation of its financial statements.

Security valuation

Investments in open-end investment companies (other than exchange-traded funds (ETFs)), are valued at the latest net asset value reported by those companies as of the valuation time.

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Notes to Financial Statements (continued)
June 30, 2022 (Unaudited)

Fund share valuation

Foreign currency transactions and translations

Securities lending

The following table indicates the total amount of securities loaned by type, reconciled to gross liability payable upon return of the securities loaned by the Fund as of June 30, 2022:

	Overnight and continuous	Up to 30 days	30-90 days	Greater than 90 days	Total
Wanger Select
Securities lending transactions
Equity securities	$1,583,464	$—	$—	$—	$1,583,464
Gross amount of recognized liabilities for securities lending (collateral received)					1,713,875
Amounts due to counterparty in the event of default					$130,411

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Notes to Financial Statements (continued)
June 30, 2022 (Unaudited)

Offsetting of assets and liabilities

	Goldman Sachs ($)
Liabilities
Collateral on Securities Loaned	1,713,875
Total Liabilities	1,713,875
Total Financial and Derivative Net Assets	(1,713,875)
Financial Instruments	1,583,464
Net Amount ^(a)	(130,411)

(a)	Represents the net amount due from/(to) counterparties in the event of default.

Security transactions and investment income

Income recognition

Expenses

Federal income tax status

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Notes to Financial Statements (continued)
June 30, 2022 (Unaudited)

Foreign taxes

Distributions to shareholders

Distributions to shareholders are recorded on the ex-dividend date.

Guarantees and indemnification

Note 3. Fees and other transactions with affiliates

Management services fees

CWAM receives a monthly advisory fee based on the Fund’s daily net assets at the following annual rates:

Average daily net assets	Annual fee rate
Up to $700 million	0.74%
$700 million to $2 billion	0.69%
$2 billion to $6 billion	0.64%
$6 billion and over	0.63%

Through April 30, 2022, CWAM had contractually agreed to waive 0.20% of the advisory fee otherwise payable to it by the Fund. When determining whether the Fund’s total expenses exceeded the contractual expense cap described below under Other expenses waived/reimbursed by the Investment Manager and its affiliates, the Fund’s net advisory fee, reflecting application of the 0.20% waiver, was used to calculate the Fund’s total expenses.

In February 2022, the Board approved a reduction in the advisory fee rates payable to the Investment Manager by the Fund. The new advisory fee, which became effective May 1, 2022, is included in the table above. Prior to May 1, 2022, the advisory fee was equal to a percentage of the Fund’s average daily net assets equal to 0.80% on the first $500 million and 0.78% for $500 million and over.

For the six months ended June 30, 2022, the annualized effective investment advisory fee rate, net of fee waivers, was 0.64% of the Fund’s average daily net assets.

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Notes to Financial Statements (continued)
June 30, 2022 (Unaudited)

Administration fees

CWAM provides administrative services and receives an administration fee from the Fund at the following annual rates:

Aggregate average daily net assets of the Trust	Annual fee rate
Up to $4 billion	0.05%
$4 billion to $6 billion	0.04%
$6 billion to $8 billion	0.03%
$8 billion and over	0.02%

Compensation of board members

Compensation of Chief Compliance Officer

Service fees

Distributor

Columbia Management Investment Distributors, Inc., a wholly owned subsidiary of Ameriprise Financial, serves as the Fund’s distributor and principal underwriter.

Other expenses waived/reimbursed by the Investment Manager and its affiliates

Effective May 1, 2022 through April 30, 2023, CWAM has contractually agreed to bear a portion of the Fund’s expenses so that its ordinary operating expenses (excluding transaction costs and certain other investment-related expenses, interest and fees on borrowings and expenses associated with the Fund’s investment in other investment companies, if any), do not

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Notes to Financial Statements (continued)
June 30, 2022 (Unaudited)

exceed the annual rate of 0.95% of the Fund’s average daily net assets. This agreement may not be modified or terminated, without approval from the Fund’s Board of Trustees and CWAM. There is no guarantee that this agreement will continue after April 30, 2023. Prior to May 1, 2022, CWAM had contractually agreed to bear a portion of the Fund’s expenses so that its ordinary operating expenses (excluding transaction costs and certain other investment-related expenses, interest and fees on borrowings and expenses associated with the Fund’s investment in other investment companies, if any), inclusive of net advisory fees, did not exceed the annual rate of 0.89% of the Fund’s average daily net assets.

Note 4. Federal tax information

At June 30, 2022, the approximate cost of all investments for federal income tax purposes and the aggregate gross approximate unrealized appreciation and depreciation based on that cost was:

Federal tax cost ($)	Gross unrealized appreciation ($)	Gross unrealized (depreciation) ($)	Net unrealized (depreciation) ($)
85,414,000	2,404,000	(19,726,000)	(17,322,000)

Tax cost of investments and unrealized appreciation/(depreciation) may also include timing differences that do not constitute adjustments to tax basis.

Note 5. Portfolio information

The aggregate cost of purchases and proceeds from sales other than short-term obligations for the six months ended June 30, 2022, were $56,067,745 and $62,270,628, respectively. The amount of purchase and sales activity impacts the portfolio turnover rate reported in the Financial Highlights.

Note 6. Affiliated money market fund

Note 7. Line of credit

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Notes to Financial Statements (continued)
June 30, 2022 (Unaudited)

overnight financing rate plus 0.11448% and (iii) the overnight bank funding rate, plus in each case, 1.00%. Each borrowing under the credit facility matures no later than 60 days after the date of borrowing. The Fund also pays a commitment fee equal to its pro rata share of the unused amount of the credit facility at a rate of 0.15% per annum. The commitment fee is included in other expenses in the Statement of Operations. This agreement expires annually in October unless extended or renewed. Prior to the October 28, 2021 amendment and restatement, the Fund had access to a revolving credit facility with a syndicate of banks led by JPMorgan Chase Bank, N.A., Citibank, N.A. and Wells Fargo Bank, N.A. which permitted collective borrowings up to $950 million. Interest was charged to each participating fund based on its borrowings at a rate equal to the higher of (i) the federal funds effective rate, (ii) the one-month London Interbank Offered Rate (LIBOR) rate and (iii) the overnight bank funding rate, plus in each case, 1.25%.

The Fund had no borrowings during the six months ended June 30, 2022.

Note 8. Significant risks

Information technology sector risk

Market risk

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Notes to Financial Statements (continued)
June 30, 2022 (Unaudited)

Shareholder concentration risk

At June 30, 2022, two unaffiliated shareholders of record owned 88.1% of the outstanding shares of the Fund in one or more accounts. The Fund has no knowledge about whether any portion of those shares was owned beneficially. Subscription and redemption activity by concentrated accounts may have a significant effect on the operations of the Fund. In the case of a large redemption, the Fund may be forced to sell investments at inopportune times, including its liquid positions, which may result in Fund losses and the Fund holding a higher percentage of less liquid positions. Large redemptions could result in decreased economies of scale and increased operating expenses for non-redeeming Fund shareholders.

Small- and mid-cap company risk

Note 9. Subsequent events

Note 10. Information regarding pending and settled legal proceedings

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Liquidity Risk Management Program

(Unaudited)

•	the Fund had sufficient liquidity to both meet redemptions and operate effectively on behalf of shareholders;
•	there were no material changes to the Program during the period;
•	the Fund’s strategy continued to be effective for an open-end mutual fund;
•	the implementation of the Program was effective to manage the Fund’s liquidity risk;
•	the Fund did not require a highly liquid investment minimum; and
•	the Program operated adequately during the period.

Board Consideration and Approval of Advisory

Agreement

(Unaudited)

Wanger Advisors Trust (the “Trust”) has an investment advisory agreement (the “Advisory Agreement”) with Columbia Wanger Asset Management, LLC (“CWAM”) under which CWAM manages Wanger Select (the “Fund”). All of the voting trustees of the Trust are persons who have no direct or indirect interest in the Advisory Agreement and are not “interested persons” (as defined in the Investment Company Act of 1940, as amended (the “1940 Act”)) of the Trust (the “Independent Trustees”). The Independent Trustees oversee the management of the Fund and, as required by law, determine at least annually whether to continue the Advisory Agreement for the Fund.

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Board Consideration and Approval of Advisory

Agreement (continued)

(Unaudited)

The materials reviewed by the Contract Committee and the Independent Trustees included, among other items: (i) information on the investment performance of the Fund relative to independently selected peer groups of funds and the Fund’s performance benchmark over various time periods, as presented and analyzed by an independent consultant; (ii) information on the Fund’s advisory fees and other expenses, including information comparing the Fund’s fees and expenses to those of a peer group of funds and information about any applicable expense limitations and fee breakpoints; (iii) data on sales and redemptions of Fund shares; and (iv) information on the profitability to CWAM and its affiliates, as well as potential “fall-out” or ancillary benefits that CWAM and its affiliates may receive as a result of their relationships with the Fund. The Contract Committee and the Board also considered other information, such as: (i) CWAM’s financial condition; (ii) the Fund’s investment objective and strategy; (iii) the overall level of resources devoted to the Fund; (iv) the size, education, experience and resources of CWAM’s investment staff and its use of technology, including with respect to the liquidity risk management program and external research and trading cost measurement tools; (v) changes in investment and other personnel at CWAM; (vi) the portfolio manager compensation framework at CWAM; (vii) the allocation of the Fund’s brokerage, and the use of “soft” commission dollars to pay for research products and services; (viii) CWAM’s risk management program; (ix) the resources devoted to, and the record of compliance with, the Fund’s investment policies and restrictions, policies on personal securities transactions and other compliance policies and procedures; (x) CWAM’s and its affiliates’ conflicts of interest; and (xi) CWAM’s management of the Fund in light of market and operating conditions arising from the COVID-19 pandemic.

Nature, quality and extent of services

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Board Consideration and Approval of Advisory

Agreement (continued)

(Unaudited)

The Independent Trustees considered that, based upon the recommendation of CWAM and Columbia Management and in anticipation of a likely future proposal to merge the Fund with and into Wanger Acorn (formerly known as Wanger USA), effective May 1, 2022, (i) the Fund’s practice of investing in a limited number of companies (generally 20-40) was discontinued, the Fund’s normal number of portfolio holdings was significantly increased and the limit on the Fund’s foreign investments was increased to align the Fund’s investment strategies and investment policies with those of Columbia Acorn Fund, a series of Columbia Acorn Trust managed by CWAM and (ii) the Fund’s advisory fee schedule was permanently reduced to align with that of Columbia Acorn Fund. The Independent Trustees noted that principal aim of CWAM and Columbia Management in implementing the changes was to improve long-term investment outcomes for shareholders of the Fund. The Independent Trustees also considered CWAM’s extensive and focused efforts to continue to improve the performance of the Fund and believed they were reasonable and appropriate.

The Independent Trustees concluded that the nature, quality and extent of the services provided by CWAM and its affiliates to the Fund under the Advisory Agreement were appropriate for the Fund and that the Fund was likely to benefit from the continued provision of those services by CWAM. They also concluded that CWAM had sufficient personnel, with appropriate education and experience, to serve the Fund effectively. The Independent Trustees considered that Ameriprise had committed to the Board that CWAM would have sufficient investment management resources to continue to improve performance, including but not limited to resources to hire investment personnel, as necessary.

Performance of the Fund

The Independent Trustees reviewed information comparing the Fund’s performance with that of the performance of comparable funds and peer groups as identified by independent consultant Broadridge Financial Solutions, Inc. (“Broadridge”) and the performance of the Fund’s primary benchmark. The Independent Trustees evaluated the performance and risk characteristics of the Fund over various periods, including over the one-, three- and five-year periods ended December 31, 2021, and April 30, 2022. The Independent Trustees considered that the Fund had underperformed its Broadridge peer group median for the one-, three- and five-year periods ended December 31, 2021. They also took into account that the Fund had outperformed its primary benchmark for the one-year period ended December 31, 2021, and underperformed its primary benchmark for the three- and five-year periods ended December 31, 2021. In addition, the Independent Trustees considered that the Fund had underperformed its Broadridge peer group median and primary benchmark for the one-, three- and five-year periods ended April 30, 2022.

Costs of services and profits realized by CWAM

The Independent Trustees examined detailed information on the fees and expenses of the Fund compared with information for similar funds provided by Broadridge. They considered that the Fund’s net total operating expenses were equal to the median of its Broadridge peer group and the Fund’s actual advisory fees were lower than the median of its Broadridge peer group. In considering the total expense levels of the Fund, the Independent Trustees also considered the total expenses of the Fund relative to its three- and five-year performance, as prepared by Broadridge. They took into account the small number of peer funds made available by Broadridge for comparison of fees and expenses.

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Board Consideration and Approval of Advisory

Agreement (continued)

(Unaudited)

The Independent Trustees also considered that while CWAM had discontinued the contractual 0.20% advisory fee waiver that had been in place for the Fund through April 30, 2021, CWAM had agreed to permanently reduce the Fund’s advisory fee schedule effective May 1, 2022. They also took into account that, effective May 1, 2022, the Fund and Wanger Acorn, another series of the Trust, as well as their Columbia Acorn Trust counterparts, Columbia Acorn Fund and Columbia Acorn USA, (together, the “Domestic Funds”), were managed in an identical manner by the same portfolio managers and that the advisory fee schedule for each of the Domestic Funds was identical.. In addition, the Independent Trustees considered that CWAM had contractually agreed through April 30, 2023 to limit the Fund’s total fees and expenses to 0.89% such that the Fund would experience a net increase in total operating expenses of only 0.06% versus the prior year in connection with the discontinuance of the former advisory fee waiver.

In addition, the Independent Trustees reviewed the analysis of CWAM’s profitability in serving as the Fund’s investment manager and of CWAM and its affiliates in their relationships with the Fund. They considered that the Contract Committee and the Board met with representatives from Ameriprise to discuss its methodologies for calculating profitability and allocating costs. They considered that Ameriprise calculated profitability and allocated costs on a contract-by-contract and fund-by-fund basis. In addition, the Independent Trustees considered an analysis of CWAM’s anticipated profitability in serving as investment manager to the funds in the Trust and Columbia Acorn Trust at various hypothetical levels of total assets. They also reviewed the methodology used by CWAM and Ameriprise to determine the level of compensation payable to portfolio managers and the competitive market for investment management talent and whether the methodology was aligned with shareholders’ interests. The Independent Trustees were provided with profitability information from a third-party consultant, Strategic Insight, which compared CWAM’s profitability to other similar investment managers in the mutual fund industry. The Independent Trustees discussed, however, that profitability comparisons among fund managers may not always be meaningful due to the lack of consistency in data, small number of publicly-owned managers, and the fact that the profitability of any investment manager is affected by numerous factors, including its particular organizational structure, the types of funds and other accounts managed, other lines of business, expense allocation methodology, capital structure and other factors. The Independent Trustees evaluated CWAM’s profitability in light of the additional resources that had been, and would continue to be, provided to the Fund by Ameriprise to assist in improving Fund performance.

Economies of scale

At various Committee and Board meetings and other informal meetings, the Independent Trustees also considered information about the extent to which CWAM realized economies of scale in connection with an increase in Fund assets. It was noted, however, that the Fund had lost assets over the past several years. The Independent Trustees noted that the advisory fee schedule for the Fund included breakpoints in the rate of fees at various asset levels. In evaluating whether CWAM was sharing economies of scale with Fund shareholders, the Independent Trustees also took into account the expense limitation that CWAM had agreed to implement for the Fund for 2022 and 2023 and CWAM’s contractual agreement to permanently reduce its advisory fee for the Fund effective May 1, 2022. The Independent Trustees concluded that the fee structure of the Advisory Agreement for the Fund reflected a sharing of economies of scale between CWAM and the Fund.

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Board Consideration and Approval of Advisory

Agreement (continued)

(Unaudited)

Other benefits to CWAM

Wanger Select | Semiannual Report 2022

Item 2. Code of Ethics.

Not applicable for semiannual reports.

Item 3. Audit Committee Financial Expert.

Not applicable for semiannual reports.

Item 4. Principal Accountant Fees and Services.

Not applicable for semiannual reports.

Item 5. Audit Committee of Listed Registrants.

Not applicable.

Item 6. Investments

(a)The registrant's "Schedule I – Investments in securities of unaffiliated issuers" (as set forth in 17 CFR 210.12-12) is included in Item 1 of this Form N-CSR.

(b)Not applicable.

Item 7. Disclosure of Proxy Voting Policies and Procedures for Closed-End Management Investment Companies.

Not applicable.

Item 8. Portfolio Managers of Closed-End Management Investment Companies.

Not applicable.

Item 9. Purchases of Equity Securities by Closed-End Management Investment Company and Affiliated Purchasers.

Not applicable.

Item 10. Submission of Matters to a Vote of Security Holders.

There were no material changes to the procedures by which shareholders may recommend nominees to the registrant's board of directors.

Item 11. Controls and Procedures.

(a)The registrant's principal executive officer and principal financial officers, based on their evaluation of the registrant's disclosure controls and procedures as of a

date within 90 days of the filing of this report, have concluded that such controls and procedures are adequately designed to ensure that information required to be disclosed by the registrant in Form N-CSR is accumulated and communicated to the registrant's management, including the principal executive officer and principal financial officer, or persons performing similar functions, as appropriate to allow timely decisions regarding required disclosure.

(b)There was no change in the registrant's internal control over financial reporting that occurred during the period covered by this report that has materially affected, or is reasonably likely to materially affect, the registrant's internal control over financial reporting.

Item 12. Disclosure of Securities Lending Activities for Closed-End Management Investment Companies

Not applicable.

Item 13. Exhibits.

(a)(1) Code of ethics required to be disclosed under Item 2 of Form N-CSR: Not applicable for semiannual reports.

(a)(2) Certifications pursuant to Rule 30a-2(a) under the Investment Company Act of 1940 (17 CFR 270.30a-2(a)) attached hereto as Exhibit 99.CERT.

(b)Certification pursuant to Rule 30a-2(b) under the Investment Company Act of 1940(17 CFR 270.30a-2(b)) attached hereto as Exhibit 99.906CERT.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly

authorized.
(registrant)			Wanger Advisors Trust
By (Signature and Title)			/s/ Daniel J. Beckman
			Daniel J. Beckman, Co-President and Principal Executive Officer
Date			August 22, 2022

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated.


By (Signature and Title)		/s/ Daniel J. Beckman
		Daniel J. Beckman, Co-President and Principal Executive Officer
Date		August 22, 2022
By (Signature and Title)		/s/ Michael G. Clarke
		Michael G. Clarke, Treasurer and Principal Accounting and Financial Officer
Date		August 22, 2022

Portfolio breakdown (%) (at June 30, 2022)
Common Stocks	94.7
Money Market Funds	3.0
Securities Lending Collateral	2.3
Total	100.0

Portfolio breakdown (%) (at June 30, 2022)
Common Stocks	94.4
Money Market Funds	3.1
Securities Lending Collateral	2.5
Total	100.0