Columbia Funds Series Trust I

Summary Prospectus

January 1, 2018

Columbia Balanced Fund

Class		Ticker Symbol
A		CBLAX
Advisor (Class Adv)^(a)		CBDRX
C		CBLCX
Institutional (Class Inst)^(a)		CBALX
Institutional 2 (Class Inst2)^(a)		CLREX
Institutional 3 (Class Inst3)^(a)		CBDYX
K ^(b)		CLRFX
R		CBLRX
T ^(c)		CBDTX

(a)	Prior to November 1, 2017, Class Adv shares were known as Class R4 shares, Class Inst shares were known as Class Z shares, Class Inst2 shares were known as Class R5 shares, and Class Inst3 shares were known as Class Y shares.
(b)	Effective on or about March 9, 2018, the shares held by Class K shareholders will be exchanged for Class Adv shares in a tax-free transaction with no impact on the fees and expenses paid by shareholders and Class K shares of the Fund will no longer be offered for sale.

(c)

Prior to March 27, 2017, Class T shares were known as Class W shares.

Before you invest, you may want to review the Fund’s prospectus, which contains more information about the Fund and its risks. You can find the Fund’s prospectus, statement of additional information and other information about the Fund online at https://www.columbiathreadneedleus.com/resources/literature. You can also get this information at no cost by calling 800.345.6611 or by sending an email to serviceinquiries@columbiathreadneedle.com. This Summary Prospectus incorporates by reference the Fund’s prospectus, dated January 1, 2018, and current Statement of Additional Information.

As with all mutual funds, the Securities and Exchange Commission has not approved or disapproved these securities or passed upon the adequacy of this prospectus. Any representation to the contrary is a criminal offense.

Investment Objective

Columbia Balanced Fund (the Fund) seeks high total return by investing in common stocks and debt securities.

Fees and Expenses of the Fund

This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund. The front-end sales charge applicable to Class T shares is a per-transaction charge, meaning that separate orders will not be aggregated for purposes of calculating the rate of the sales charge payable. An investor transacting in a class of Fund shares without any front-end sales charge, contingent deferred sales charge, or other asset-based fee for sales or distribution may be required to pay a commission to the financial intermediary for effecting such transactions. Such commission rates are set by the financial intermediary and are not reflected in the tables or the example below. You may qualify for sales charge discounts if you and members of your immediate family invest, or agree to invest in the future, at least $50,000 in certain classes of shares of eligible funds distributed by Columbia Management Investment Distributors, Inc. (the Distributor). More information about these and other sales charge discounts and waivers is available from your financial intermediary, and can be found in the Choosing a Share Class section beginning on page 28 of the Fund’s prospectus, in Appendix A to the prospectus beginning on page A-1 and in Appendix S to the Statement of Additional Information (SAI) under Sales Charge Waivers beginning on page S-1.

Shareholder Fees (fees paid directly from your investment)
	Class A	Class C	Class T	Classes Adv, Inst, Inst2, Inst3, K and R
Maximum sales charge (load) imposed on purchases (as a % of offering price)	5.75%	None	2.50%	None
Maximum deferred sales charge (load) imposed on redemptions (as a % of the lower of the original purchase price or current net asset value)	1.00% ^(a)	1.00% ^(b)	None	None

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
	Class A	Class Adv	Class C	Class Inst	Class Inst2	Class Inst3	Class K	Class R	Class T
Management fees	0.58%	0.58%	0.58%	0.58%	0.58%	0.58%	0.58%	0.58%	0.58%
Distribution and/or service (12b-1) fees	0.25%	0.00%	1.00%	0.00%	0.00%	0.00%	0.00%	0.50%	0.25%
Other expenses^(c)	0.13%	0.13%	0.13%	0.13%	0.08%	0.03%	0.33%	0.13%	0.13%
Total annual Fund operating expenses	0.96%	0.71%	1.71%	0.71%	0.66%	0.61%	0.91%	1.21%	0.96%

(a)	This charge is imposed on certain investments of between $1 million and $50 million redeemed within 18 months after purchase, as follows: 1.00% if redeemed within 12 months after purchase, and 0.50% if redeemed more than 12, but less than 18, months after purchase, with certain limited exceptions.
(b)	This charge applies to redemptions within 12 months after purchase, with certain limited exceptions.
(c)	Other expenses have been restated to reflect current transfer agency fees paid by the Fund and other expenses for Class T shares are based on estimated amounts for the Fund’s current fiscal year.

Example

The following example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The example illustrates the hypothetical expenses that you would incur over the time periods indicated, and assumes that:

■	you invest $10,000 in the applicable class of Fund shares for the periods indicated,
■	your investment has a 5% return each year, and
■	the Fund’s total annual operating expenses remain the same as shown in the Annual Fund Operating Expenses table above.

1	Columbia Balanced Fund

Although your actual costs may be higher or lower, based on the assumptions listed above, your costs would be:

	1 year	3 years	5 years	10 years
Class A (whether or not shares are redeemed)	$667	$863	$1,075	$1,685
Class Adv (whether or not shares are redeemed)	$ 73	$227	$ 395	$ 883
Class C (assuming redemption of all shares at the end of the period)	$274	$539	$ 928	$2,019
Class C (assuming no redemption of shares)	$174	$539	$ 928	$2,019
Class Inst (whether or not shares are redeemed)	$ 73	$227	$ 395	$ 883
Class Inst2 (whether or not shares are redeemed)	$ 67	$211	$ 368	$ 822
Class Inst3 (whether or not shares are redeemed)	$ 62	$195	$ 340	$ 762
Class K (whether or not shares are redeemed)	$ 93	$290	$ 504	$1,120
Class R (whether or not shares are redeemed)	$123	$384	$ 665	$1,466
Class T (whether or not shares are redeemed)	$345	$548	$ 768	$1,399

Portfolio Turnover

The Fund may pay transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 63% of the average value of its portfolio.

Principal Investment Strategies

Under normal circumstances, the Fund invests in a mix of equity and debt securities. The Fund’s assets are allocated among equity and debt securities (which includes cash and cash equivalents) based on an assessment of the relative risks and returns of each asset class. The Fund generally will invest between 35% and 65% of its net assets in each asset class, and in any event will invest at least 25% and no more than 75% of its net assets in each asset class under normal circumstances.

With respect to its equity securities investments, which may include among other types of equity securities, common stocks, preferred stocks and securities convertible into common or preferred stocks, the Fund invests primarily in equity securities of companies that, at the time of purchase, have large market capitalizations (generally over $5 billion).

With respect to its debt securities investments, the Fund invests primarily in securities that, at the time of purchase, are rated investment grade or are unrated but determined to be of comparable quality. These securities include debt securities issued by the U.S. Government and its agencies and instrumentalities, debt securities issued by corporations, mortgage- and other asset-backed securities, and other debt securities with intermediate- to long-term maturities. The Fund may invest up to 10% of its total assets in debt instruments that, at the time of purchase, are rated below investment grade or are unrated but determined to be of comparable quality (commonly referred to as “high-yield” investments or “junk” bonds).

The Fund may also invest up to 20% of its net assets in foreign securities. The Fund may invest directly in foreign securities or indirectly through depositary receipts.

The Fund may invest in derivatives, such as futures (including interest rate futures). The Fund may invest in derivatives for both hedging and non-hedging (investment) purposes, including, for example, to seek to enhance returns or as a substitute for a position in an underlying asset, as well as to manage duration, yield curve and/or interest rate exposure.

The Fund may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis. Such securities may include mortgage-backed securities acquired or sold in the “to be announced” (TBA) market and those in a dollar roll transaction.

The Fund’s investment strategy may involve the frequent trading of portfolio securities.

Principal Risks

An investment in the Fund involves risks, including those described below. There is no assurance that the Fund will achieve its investment objective and you may lose money. The value of the Fund’s holdings may decline, and the Fund’s net asset value (NAV) and share price may go down. An investment in the Fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

Columbia Balanced Fund

Active Management Risk. Due to its active management, the Fund could underperform its benchmark index and/or other funds with similar investment objectives and/or strategies.

Allocation Risk. Because the Fund uses an asset allocation strategy in pursuit of its investment objective, there is a risk that the Fund's allocation among asset classes, investments, strategies and/or investment styles will cause the Fund's shares to lose value or cause the Fund to underperform other funds with similar investment objectives and/or strategies, or that the investments themselves will not produce the returns expected.

Convertible Securities Risk. Convertible securities are subject to the usual risks associated with debt instruments, such as interest rate risk and credit risk. Convertible securities also react to changes in the value of the common stock into which they convert, and are thus subject to market risk. The Fund may also be forced to convert a convertible security at an inopportune time, which may decrease the Fund’s return.

Credit Risk. Credit risk is the risk that the value of debt instruments may decline if the issuer thereof defaults or otherwise becomes unable or unwilling, or is perceived to be unable or unwilling, to honor its financial obligations, such as making payments to the Fund when due. Rating agencies assign credit ratings to certain debt instruments to indicate their credit risk. Unless otherwise provided in the Fund’s Principal Investment Strategies, investment grade debt instruments are those rated at or above BBB- by Standard and Poor’s Ratings Services, or equivalently rated by Moody’s Investors Service, Inc. or Fitch, Inc., or, if unrated, determined to be of comparable quality. Conversely, below investment grade (commonly called “high-yield” or “junk”) debt instruments are those rated below BBB- (or its equivalent) by such agencies or, if unrated, determined to be of comparable quality. A rating downgrade by such agencies can negatively impact the value of such instruments. Lower quality or unrated instruments held by the Fund may present increased credit risk as compared to higher-rated instruments. Non-investment grade debt instruments may be subject to greater price fluctuations and are more likely to experience a default than investment grade debt instruments and therefore may expose the Fund to increased credit risk. If the Fund purchases unrated instruments, or if the ratings of instruments held by the Fund are lowered after purchase, the Fund will depend on analysis of credit risk more heavily than usual.

Depositary Receipts Risk. Depositary receipts are receipts issued by a bank or trust company reflecting ownership of underlying securities issued by foreign companies. Some foreign securities are traded in the form of American Depositary Receipts and/or Global Depositary Receipts. Depositary receipts involve risks similar to the risks associated with investments in foreign securities, including those associated with investing in the particular country of an issuer, which may be related to the particular political, regulatory, economic, social and other conditions or events, including, for example, military confrontations, war and terrorism, occurring in the country and fluctuations in its currency, as well as market risk tied to the underlying foreign company. In addition, depositary receipt holders may have limited voting rights, may not have the same rights afforded typical company stockholders in the event of a corporate action such as an acquisition, merger or rights offering and may experience difficulty in receiving company stockholder communications. There is no guarantee that a financial institution will continue to sponsor depositary receipts, or that the depositary receipts will continue to trade on an exchange, either of which could adversely affect the liquidity, availability and pricing of the depositary receipt. Changes in foreign currency exchange rates will affect the value of depositary receipts and, therefore, may affect the value of the Fund's portfolio.

Derivatives Risk. Derivatives may involve significant risks. Derivatives are financial instruments with a value in relation to, or derived from, the value of an underlying asset(s) or other reference, such as an index, rate or other economic indicator (each an underlying reference). Derivatives may include those that are privately placed or otherwise exempt from SEC registration, including certain Rule 144A eligible securities. Derivatives could result in Fund losses if the underlying reference does not perform as anticipated. Use of derivatives is a highly specialized activity that can involve investment techniques, risks, and tax planning different from those associated with more traditional investment instruments. The Fund’s derivatives strategy may not be successful and use of certain derivatives could result in substantial, potentially unlimited, losses to the Fund regardless of the Fund’s actual investment. A relatively small movement in the price, rate or other economic indicator associated with the underlying reference may result in substantial loss for the Fund. Derivatives may be more volatile than other types of investments. The value of derivatives may be influenced by a variety of factors, including national and international political and economic developments. Potential changes to the regulation of the derivatives markets may make derivatives more costly, may limit the market for derivatives, or may otherwise adversely affect the value or performance of derivatives. Derivatives can increase the Fund’s risk exposure to underlying references and their attendant risks, such as credit risk, market risk, foreign currency risk and interest rate risk, while exposing the Fund to correlation risk, counterparty risk, hedging risk, leverage risk, liquidity risk, pricing risk and volatility risk.

Derivatives Risk – Futures Contracts Risk. A futures contract is an exchange-traded derivative transaction between two parties in which a buyer (holding the “long” position) agrees to pay a fixed price (or rate) at a specified future date for delivery of an underlying reference from a seller (holding the “short” position). The seller hopes that the market price on the delivery date is less than the agreed upon price, while the buyer hopes for the contrary. Certain

3	Columbia Balanced Fund

futures contract markets are highly volatile, and futures contracts may be illiquid. Futures exchanges may limit fluctuations in futures contract prices by imposing a maximum permissible daily price movement. The Fund may be disadvantaged if it is prohibited from executing a trade outside the daily permissible price movement. At or prior to maturity of a futures contract, the Fund may enter into an offsetting contract and may incur a loss to the extent there has been adverse movement in futures contract prices. The liquidity of the futures markets depends on participants entering into offsetting transactions rather than making or taking delivery. To the extent participants make or take delivery, liquidity in the futures market could be reduced. As a result, a relatively small price movement in a futures contract may result in substantial losses to the Fund, exceeding the amount of the margin paid. For certain types of futures contracts, losses are potentially unlimited. Futures markets are highly volatile and the use of futures may increase the volatility of the Fund’s NAV. Futures contracts executed (if any) on foreign exchanges may not provide the same protection as U.S. exchanges. Futures contracts can increase the Fund’s risk exposure to underlying references and their attendant risks, such as credit risk, market risk, foreign currency risk and interest rate risk, while also exposing the Fund to correlation risk, counterparty risk, hedging risk, leverage risk, liquidity risk, pricing risk and volatility risk.

Foreign Securities Risk. Investments in or exposure to foreign securities involve certain risks not associated with investments in or exposure to securities of U.S. companies. Foreign securities subject the Fund to the risks associated with investing in the particular country of an issuer, including political, regulatory, economic, social, diplomatic and other conditions or events (including, for example, military confrontations, war and terrorism), occurring in the country or region, as well as risks associated with less developed custody and settlement practices. Foreign securities may be more volatile and less liquid than securities of U.S. companies, and are subject to the risks associated with potential imposition of economic and other sanctions against a particular foreign country, its nationals or industries or businesses within the country. In addition, foreign governments may impose withholding or other taxes on the Fund’s income, capital gains or proceeds from the disposition of foreign securities, which could reduce the Fund’s return on such securities. The performance of the Fund may also be negatively affected by fluctuations in a foreign currency's strength or weakness relative to the U.S. dollar, particularly to the extent the Fund invests a significant percentage of its assets in foreign securities or other assets denominated in currencies other than the U.S. dollar.

Forward Commitments on Mortgage-Backed Securities (including Dollar Rolls) Risk. When purchasing mortgage-backed securities in the “to be announced” (TBA) market (MBS TBAs), the seller agrees to deliver mortgage-backed securities for an agreed upon price on an agreed upon date, but may make no guarantee as to the specific securities to be delivered. In lieu of taking delivery of mortgage-backed securities, the Fund could enter into dollar rolls, which are transactions in which the Fund sells securities to a counterparty and simultaneously agrees to purchase those or similar securities in the future at a predetermined price. Dollar rolls involve the risk that the market value of the securities the Fund is obligated to repurchase may decline below the repurchase price, or that the counterparty may default on its obligations. These transactions may also increase the Fund’s portfolio turnover rate. If the Fund reinvests the proceeds of the security sold, the Fund will also be subject to the risk that the investments purchased with such proceeds will decline in value (a form of leverage risk). MBS TBAs and dollar rolls are subject to the risk that the counterparty to the transaction may not perform or be unable to perform in accordance with the terms of the instrument.

Frequent Trading Risk. The portfolio managers may actively and frequently trade investments in the Fund's portfolio to carry out its investment strategies. Frequent trading of investments increases the possibility that the Fund, as relevant, will realize taxable capital gains (including short-term capital gains, which are generally taxable to shareholders at higher rates than long-term capital gains for U.S. federal income tax purposes), which could reduce the Fund's after-tax return. Frequent trading can also mean higher brokerage and other transaction costs, which could reduce the Fund's return. The trading costs and tax effects associated with portfolio turnover may adversely affect the Fund’s performance.

High-Yield Investments Risk. Securities and other debt instruments held by the Fund that are rated below investment grade (commonly called “high-yield” or “junk” bonds) and unrated debt instruments of comparable quality expose the Fund to a greater risk of loss of principal and income than a fund that invests solely or primarily in investment grade debt instruments. In addition, these investments have greater price fluctuations, are less liquid and are more likely to experience a default than higher-rated debt instruments. High-yield debt instruments are considered to be predominantly speculative with respect to the issuer’s capacity to pay interest and repay principal.

Interest Rate Risk. Interest rate risk is the risk of losses attributable to changes in interest rates. In general, if prevailing interest rates (which are currently near historic lows) rise, the values of debt instruments tend to fall, and if interest rates fall, the values of debt instruments tend to rise. Changes in the value of a debt instrument usually will not affect the amount of income the Fund receives from it but will generally affect the value of the Fund's shares. In general, the longer the maturity or duration of a debt instrument, the greater its sensitivity to changes in interest

Columbia Balanced Fund

rates. Interest rate declines also may increase prepayments of debt obligations, which, in turn, would increase prepayment risk. Similarly, a period of rising interest rates may negatively impact the Fund’s performance. Actions by governments and central banking authorities can result in increases in interest rates. Such actions may negatively affect the value of debt instruments held by the Fund, resulting in a negative impact on the Fund's performance and NAV. Any interest rate increases could cause the value of the Fund’s investments in debt instruments to decrease. Rising interest rates may prompt redemptions from the Fund, which may force the Fund to sell investments at a time when it is not advantageous to do so, which could result in losses.

Issuer Risk. An issuer in which the Fund invests or to which it has exposure may perform poorly, and the value of its securities may therefore decline, which would negatively affect the Fund’s performance. Poor performance may be caused by poor management decisions, competitive pressures, breakthroughs in technology, reliance on suppliers, labor problems or shortages, corporate restructurings, fraudulent disclosures, natural disasters or other events, conditions or factors.

Liquidity Risk. Liquidity risk is the risk associated with any event, circumstance, or characteristic of an investment or market that negatively impacts the Fund’s ability to sell, or realize the proceeds from the sale of, an investment at a desirable time or price. Liquidity risk may arise because of, for example, a lack of marketability of the investment, which means that when seeking to sell its portfolio investments, the Fund could find that selling is more difficult than anticipated, especially during times of high market volatility. Decreases in the number of financial institutions, including banks and broker-dealers, willing to make markets (match up sellers and buyers) in the Fund’s investments or decreases in their capacity or willingness to trade such investments may increase the Fund’s exposure to this risk. The debt market has experienced considerable growth, and financial institutions making markets in instruments purchased and sold by the Fund (e.g., bond dealers) have been subject to increased regulation. The impact of that growth and regulation on the ability and willingness of financial institutions to engage in trading or “making a market” in such instruments remains unsettled. Certain types of investments, such as lower-rated securities or those that are purchased and sold in over-the-counter markets, may be especially subject to liquidity risk. Securities or other assets in which the Fund invests may be traded in the over-the-counter market rather than on an exchange and therefore may be more difficult to purchase or sell at a fair price, which may have a negative impact on the Fund’s performance. Market participants attempting to sell the same or a similar instrument at the same time as the Fund could exacerbate the Fund’s exposure to liquidity risk. The Fund may have to accept a lower selling price for the holding, sell other liquid or more liquid investments that it might otherwise prefer to hold (thereby increasing the proportion of the Fund’s investments in less liquid or illiquid securities), or forego another more appealing investment opportunity. Certain investments that were liquid when purchased by the Fund may later become illiquid, particularly in times of overall economic distress. Changing regulatory, market or other conditions or environments (for example, the interest rate or credit environments) may also adversely affect the liquidity and the price of the Fund's investments. Judgment plays a larger role in valuing illiquid or less liquid investments as compared to valuing liquid or more liquid investments. Price volatility may be higher for illiquid or less liquid investments as a result of, for example, the relatively less frequent pricing of such securities (as compared to liquid or more liquid investments). Generally, the less liquid the market at the time the Fund sells a portfolio investment, the greater the risk of loss or decline of value to the Fund. Overall market liquidity and other factors can lead to an increase in redemptions, which may negatively impact Fund performance and NAV, including, for example, if the Fund is forced to sell investments in a down market.

Market Risk. Market risk refers to the possibility that the market values of securities or other investments that the Fund holds will fall, sometimes rapidly or unpredictably, or fail to rise. An investment in the Fund could lose money over short or long periods.

Mortgage- and Other Asset-Backed Securities Risk. The value of any mortgage-backed and other asset-backed securities held by the Fund may be affected by, among other things, changes or perceived changes in: interest rates; factors concerning the interests in and structure of the issuer or the originator of the mortgages or other assets; the creditworthiness of the entities that provide any supporting letters of credit, surety bonds or other credit enhancements; or the market's assessment of the quality of underlying assets. Payment of principal and interest on some mortgage-backed securities (but not the market value of the securities themselves) may be guaranteed by the full faith and credit of a particular U.S. Government agency, authority, enterprise or instrumentality, and some, but not all, are also insured or guaranteed by the U.S. Government. Mortgage-backed securities issued by non-governmental issuers (such as commercial banks, savings and loan institutions, private mortgage insurance companies, mortgage bankers and other secondary market issuers) may entail greater risk than obligations guaranteed by the U.S. Government. Mortgage- and other asset-backed securities are subject to prepayment risk, which is the possibility that the underlying mortgage or other asset may be refinanced or prepaid prior to maturity during periods of declining or low interest rates, causing the Fund to have to reinvest the money received in securities that have lower yields. Rising or high interest rates tend to extend the duration of mortgage- and other asset-backed securities, making their prices more volatile and more sensitive to changes in interest rates.

5	Columbia Balanced Fund

Preferred Stock Risk. Preferred stock is a type of stock that generally pays dividends at a specified rate and that has preference over common stock in the payment of dividends and the liquidation of assets. Preferred stock does not ordinarily carry voting rights. The price of a preferred stock is generally determined by earnings, type of products or services, projected growth rates, experience of management, liquidity, and general market conditions of the markets on which the stock trades. The most significant risks associated with investments in preferred stock include issuer risk, market risk and interest rate risk (i.e., the risk of losses attributable to changes in interest rates).

Prepayment and Extension Risk. Prepayment and extension risk is the risk that a bond or other security or investment might, in the case of prepayment risk, be called or otherwise converted, prepaid or redeemed before maturity and, in the case of extension risk, that the investment might not be called as expected. In the case of prepayment risk, if the investment is converted, prepaid or redeemed before maturity, the portfolio managers may not be able to invest the proceeds in other investments providing as high a level of income, resulting in a reduced yield to the Fund. In the case of mortgage- or asset-backed securities, as interest rates decrease or spreads narrow, the likelihood of prepayment increases. Conversely, extension risk is the risk that an unexpected rise in interest rates will extend the life of a mortgage- or asset-backed security beyond the prepayment time. If the Fund’s investments are locked in at a lower interest rate for a longer period of time, the portfolio managers may be unable to capitalize on securities with higher interest rates or wider spreads.

Reinvestment Risk. Reinvestment risk is the risk that the Fund will not be able to reinvest income or principal at the same return it is currently earning.

U.S. Government Obligations Risk. While U.S. Treasury obligations are backed by the “full faith and credit” of the U.S. Government, such securities are nonetheless subject to credit risk (i.e., the risk that the U.S. Government may be, or be perceived to be, unable or unwilling to honor its financial obligations, such as making payments). Securities issued or guaranteed by federal agencies or authorities and U.S. Government-sponsored instrumentalities or enterprises may or may not be backed by the full faith and credit of the U.S. Government.

Value Securities Risk. Value securities are securities of companies that may have experienced, for example, adverse business, industry or other developments or may be subject to special risks that have caused the securities to be out of favor and, in turn, potentially undervalued. The market value of a portfolio security may not meet portfolio management’s perceived value assessment of that security, or may decline in price, even though portfolio management believes the securities are already undervalued. There is also a risk that it may take longer than expected for the value of these investments to rise to portfolio management’s perceived value. In addition, value securities, at times, may not perform as well as growth securities or the stock market in general, and may be out of favor with investors for varying periods of time.

Performance Information

The following bar chart and table show you how the Fund has performed in the past, and can help you understand the risks of investing in the Fund. Class T shares of the Fund commenced operations after the periods shown in the table below and, therefore, performance information is not yet available. The bar chart shows how the Fund’s Class A share performance (without sales charges) has varied for each full calendar year shown. If the sales charges were reflected, returns shown would be lower. The table below the bar chart compares the Fund’s returns (after applicable sales charges shown in the Shareholder Fees table in this prospectus) for the periods shown with a blended benchmark that is intended to provide a measure of the Fund's performance given its investment strategy, as well as one or more other measures of performance for markets in which the Fund may invest.

The performance of one or more share classes shown in the table below begins before the indicated inception date for such share class. The returns shown for each such share class include the returns of the Fund’s Class Inst shares (adjusted to reflect the higher class-related operating expenses of such classes, where applicable) for periods prior to its inception date. Any share class, such as Class T shares, that does not have available performance would have annual returns substantially similar to those of Class A shares. Except for differences in annual returns resulting from differences in expenses and sales charges (where applicable), the share classes of the Fund would have substantially similar annual returns because all share classes of the Fund invest in the same portfolio of securities.

The after-tax returns shown in the Average Annual Total Returns table below are calculated using the highest historical individual U.S. federal marginal income tax rates and do not reflect the impact of state, local or foreign taxes. Your actual after-tax returns will depend on your personal tax situation and may differ from those shown in the table. In addition, the after-tax returns shown in the table do not apply to shares held in tax-advantaged accounts such as 401(k) plans or Individual Retirement Accounts (IRAs). The after-tax returns are shown only for Class A shares and will vary for other share classes. Returns after taxes on distributions and sale of Fund shares are higher than before-tax returns for certain periods shown because they reflect the tax benefit of capital losses realized on the redemption of Fund shares.

Columbia Balanced Fund

The Fund’s past performance (before and after taxes) is no guarantee of how the Fund will perform in the future. Updated performance information can be obtained by calling toll-free 800.345.6611 or visiting columbiathreadneedle.com/us.

Year by Year Total Return (%) as of December 31 Each Year*	Best and Worst Quarterly Returns During the Period Shown in the Bar Chart
	_Best	_{2nd Quarter 2009}	_14.13%
	_Worst	_{4th Quarter 2008}	_-14.09%

*	Year to Date return as of September 30, 2017: 10.22%

Average Annual Total Returns After Applicable Sales Charges (for periods ended December 31, 2016)

	Share Class Inception Date	1 Year	5 Years	10 Years
Class A	11/01/2002
returns before taxes		0.05%	8.98%	6.54%
returns after taxes on distributions		-0.27%	8.41%	5.93%
returns after taxes on distributions and sale of Fund shares		0.29%	7.07%	5.15%
Class Adv returns before taxes	11/08/2012	6.40%	10.56%	7.44%
Class C returns before taxes	10/13/2003	4.35%	9.46%	6.37%
Class Inst returns before taxes	10/01/1991	6.43%	10.55%	7.44%
Class Inst2 returns before taxes	03/07/2011	6.50%	10.67%	7.50%
Class Inst3 returns before taxes	11/08/2012	6.58%	10.71%	7.51%
Class K returns before taxes	03/07/2011	6.24%	10.38%	7.23%
Class R returns before taxes	09/27/2010	5.89%	10.02%	6.90%
Blended Benchmark (consisting of 60% S&P 500® Index and 40% Bloomberg Barclays U.S. Aggregate Bond Index) (reflects no deductions for fees, expenses or taxes)		8.31%	9.69%	6.21%
S&P 500® Index (reflects no deductions for fees, expenses or taxes)		11.96%	14.66%	6.95%
Bloomberg Barclays U.S. Aggregate Bond Index (reflects no deductions for fees, expenses or taxes)		2.65%	2.23%	4.34%

Fund Management

Investment Manager: Columbia Management Investment Advisers, LLC

Portfolio Manager	Title	Role with Fund	Managed Fund Since
Guy Pope, CFA	Senior Portfolio Manager and Head of Contrarian Core Strategy	Co-Lead Portfolio Manager	1997
Leonard Aplet, CFA	Senior Portfolio Manager and Head of Short Duration and Stable Value	Co-Lead Portfolio Manager	1991
Brian Lavin, CFA	Senior Portfolio Manager	Co-Portfolio Manager	2010
Gregory Liechty	Senior Portfolio Manager	Co-Portfolio Manager	2011
Ronald Stahl, CFA	Senior Portfolio Manager	Co-Portfolio Manager	2005

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Purchase and Sale of Fund Shares

You may purchase or redeem shares of the Fund on any business day by contacting the Fund in the ways described below:

Online		Regular Mail		Express Mail		By Telephone
investor.columbiathreadneedle.com/us		Columbia Funds, c/o Columbia Management Investment Services Corp. P.O. Box 8081 Boston, MA 02266-8081		Columbia Funds, c/o Columbia Management Investment Services Corp. 30 Dan Road, Suite 8081 Canton, MA 02021-2809		800.422.3737

You may purchase shares and receive redemption proceeds by electronic funds transfer, by check or by wire. If you maintain your account with a broker-dealer or other financial intermediary, you must contact that financial intermediary to buy, sell or exchange shares of the Fund through your account with the intermediary.

The minimum initial investment amounts for the share classes offered by the Fund are shown below:

Minimum Initial Investment

Class	Category of eligible account	For accounts other than systematic investment plan accounts	For systematic investment plan accounts
Classes A, C & T^(a)	All accounts other than IRAs	$2,000	$100
Classes A, C & T^(a)	IRAs	$1,000	$100
Classes Adv & Inst	All eligible accounts	$0, $1,000 or $2,000 depending upon the category of eligible investor	$100
Classes Inst2, K^(b) & R	All eligible accounts	None	N/A
Class Inst3	All eligible accounts	$0, $1,000, $2,000 or $1 million depending upon the category of eligible investor	$100 (for certain eligible investors)

(a)	Class T shares must be purchased through financial intermediaries that, by written agreement with Columbia Management Investment Distributors, Inc., are specifically authorized to sell Class T shares.

(b)	Class K shares are generally closed to new investors.

There is no minimum additional investment for any share class.

Tax Information

The Fund normally distributes net investment income and net realized capital gains, if any, to shareholders. These distributions are generally taxable to you as ordinary income, qualified dividend income or capital gains, unless you are investing through a tax-advantaged account, such as a 401(k) plan or an IRA. If you are investing through a tax-advantaged account, you may be taxed upon withdrawals from that account.

Payments to Broker-Dealers and Other Financial Intermediaries

If you purchase the Fund through a broker-dealer or other financial intermediary (such as a bank), the Fund and its related companies — including Columbia Management Investment Advisers, LLC (the Investment Manager), Columbia Management Investment Distributors, Inc. (the Distributor) and Columbia Management Investment Services Corp. (the Transfer Agent) — may pay the intermediary for the sale of Fund shares and related services. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your financial advisor to recommend the Fund over another investment. Ask your financial advisor or visit your financial intermediary’s website for more information.

Columbia Balanced Fund

Columbia Threadneedle Investments is the global brand name of the Columbia and Threadneedle group of companies.

columbiathreadneedle.com/us

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