Balanced Fund

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Janus Henderson Balanced Fund

Ticker:	JDBAX	Class A Shares	JABRX	Class S Shares	JABNX	Class N Shares	JABAX	Class T Shares
	JABCX	Class C Shares	JBALX	Class I Shares	JDBRX	Class R Shares

Summary Prospectus dated January 28, 2022

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, reports to shareholders, and other information about the Fund online at janushenderson.com/info. You can also get this information at no cost by calling a Janus Henderson representative at 1-877-335-2687 or by sending an email request to prospectusrequest@janushenderson.com.

Investment Objective

Janus Henderson Balanced Fund seeks long-term capital growth, consistent with preservation of capital and balanced by current income.

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. Each share class has different expenses, but represents an investment in the same Fund. For Class A Shares, you may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the Fund or in other Janus Henderson mutual funds. More information about these and other discounts, as well as eligibility requirements for each share class, is available from your financial professional and in the “Purchases” section on page 97 of the Fund’s Prospectus and in the “Purchases” section on page 82 of the Fund’s Statement of Additional Information. In addition, please see Appendix A – Intermediary Sales Charge Waivers and Discounts. You may also incur brokerage commissions charged by your broker or financial intermediary when buying Class I Shares or Class N Shares of the Fund that are not reflected in the table or in the example below.

SHAREHOLDER FEES (fees paid directly from your investment)	Class A	Class C	Class S	Class I	Class N	Class R	Class T
Maximum Sales Charge (load) Imposed on Purchases (as a percentage of offering price)	5.75%	None	None	None	None	None	None
Maximum Deferred Sales Charge (load) (as a percentage of the lower of original purchase price or redemption proceeds)	None	1.00%	None	None	None	None	None
ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)	Class A	Class C	Class S	Class I	Class N	Class R	Class T
Management Fees	0.55%	0.55%	0.55%	0.55%	0.55%	0.55%	0.55%
Distribution/Service (12b-1) Fees	0.25%	1.00%	0.25%	None	None	0.50%	None
Other Expenses	0.09%	0.08%	0.27%	0.10%	0.02%	0.27%	0.27%
Total Annual Fund Operating Expenses	0.89%	1.63%	1.07%	0.65%	0.57%	1.32%	0.82%

EXAMPLE:

The 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 assumes that you invest $10,000 in the Fund for the time periods indicated and reinvest all dividends and distributions. The Example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same. Class C Shares automatically convert to Class A Shares after eight years. The Example for Class C Shares for the ten-year period reflects the conversion to Class A Shares. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

If Shares are redeemed:	1 Year	3 Years	5 Years	10 Years
Class A Shares	$ 661	$ 843	$ 1,040	$ 1,608
Class C Shares	$ 266	$ 514	$ 887	$ 1,735
Class S Shares	$ 109	$ 340	$ 590	$ 1,306
Class I Shares	$ 66	$ 208	$ 362	$ 810
Class N Shares	$ 58	$ 183	$ 318	$ 714

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If Shares are redeemed:	1 Year	3 Years	5 Years	10 Years
Class R Shares	$ 134	$ 418	$ 723	$ 1,590
Class T Shares	$ 84	$ 262	$ 455	$ 1,014

If Shares are not redeemed:	1 Year	3 Years	5 Years	10 Years
Class A Shares	$ 661	$ 843	$ 1,040	$ 1,608
Class C Shares	$ 166	$ 514	$ 887	$ 1,735
Class S Shares	$ 109	$ 340	$ 590	$ 1,306
Class I Shares	$ 66	$ 208	$ 362	$ 810
Class N Shares	$ 58	$ 183	$ 318	$ 714
Class R Shares	$ 134	$ 418	$ 723	$ 1,590
Class T Shares	$ 84	$ 262	$ 455	$ 1,014

Portfolio Turnover: The Fund pays 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 60% of the average value of its portfolio.

Principal investment strategies

The Fund pursues its investment objective by normally investing 35-65% of its assets in equity securities and the remaining assets in fixed-income securities and cash equivalents. The Fund normally invests at least 25% of its assets in fixed-income senior securities. As of September 30, 2021, approximately 63.70% of the Fund’s assets were held in equity securities, including common stocks and preferred stocks, and 36.30% of the Fund’s assets were held in fixed-income securities and cash equivalents.

The Fund’s equity investments include, but are not limited to, common stocks, preferred stocks, and other securities with equity characteristics. The Fund’s fixed-income investments include, but are not limited to, government notes and bonds, corporate bonds, commercial and residential mortgage-backed securities, and asset-backed securities. The Fund may also invest in money market instruments and commercial loans (such as bank loans). The Fund may invest in fixed and floating rate obligations with varying durations.

The Fund will limit its investments in high-yield/high-risk bonds (also known as “junk” bonds) to 35% of the fixed-income portion of its net assets. The Fund may enter into “to be announced” or “TBA” commitments when purchasing mortgage-backed securities or other securities. The Fund may also invest in securities that cannot be offered for public resale unless registered under the applicable securities laws or that have a contractual restriction that prohibits or limits their resale (these are know as “restricted securities”). The Fund may also invest in foreign securities, which may include investments in emerging market securities.

The Fund may also invest its assets in derivatives, which are instruments that have a value derived from, or directly linked to, an underlying asset, such as equity securities, fixed-income securities, commodities, currencies, interest rates, or market indices. In particular, the Fund may use forward currency contracts to offset risks associated with an investment, currency exposure, or market conditions and may use interest rate swaps and futures, including Treasury bond futures, to manage interest rate risk, yield curve positioning, and country exposure. The Fund may also use index credit default swaps for hedging purposes (to offset risks associated with an investment exposure, or market conditions), to increase or decrease the Fund’s exposure to a particular market, to manage or adjust the risk profile of the Fund relative to its benchmark index, and to earn income, enhance returns, or preserve capital. The Fund’s exposure to derivatives will vary, and may include derivatives that have characteristics similar to the securities in which the Fund may directly invest. The Fund may invest in short sales of derivatives instruments.

The portfolio managers share day-to-day responsibility for the Fund’s investments. In choosing investments for the Fund, the portfolio manager who focuses on the equity portion of the Fund applies a “bottom up” approach. In other words, the portfolio manager looks at companies one at a time to determine if a company is an attractive investment opportunity and if it is consistent with the Fund’s investment policies. Factors that the equity portfolio manager may consider in his fundamental analysis include a company’s revenue growth potential, returns on capital, and balance sheet flexibility. The equity portfolio

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manager may generally consider selling a security when, among other things, it reaches or exceeds its targeted value, the investment thesis for owning the position has changed, or to rebalance industry or sector weightings.

The portfolio managers who focus on the fixed-income portion of the Fund use research-driven, “top-down” and “bottom-up” factors to identify and manage exposure to risks across sectors, industries, and individual investments. The fixed-income portfolio managers evaluate expected risk-adjusted returns on a portfolio and position level by analyzing fundamentals, valuations, and market technical indicators.

The Fund may lend portfolio securities on a short-term or long-term basis, in an amount equal to up to one-third of its total assets of its fixed-income investments as determined at the time of the loan origination.

Principal investment risks

The biggest risk is that the Fund’s returns will vary, and you could lose money. The Fund is designed for long-term investors seeking a balanced portfolio, including common stocks and bonds. Common stocks tend to be more volatile than many other investment choices. The principal risks associated with investing in the Fund are set forth below.

Market Risk. The value of the Fund’s portfolio may decrease if the value of an individual company or security, or multiple companies or securities, in the portfolio decreases or if the portfolio managers’ belief about a company’s intrinsic worth is incorrect. Further, regardless of how well individual companies or securities perform, the value of the Fund’s portfolio could also decrease if there are deteriorating economic or market conditions. It is important to understand that the value of your investment may fall, sometimes sharply, in response to changes in the market, and you could lose money. Market risk may affect a single issuer, industry, economic sector, or the market as a whole. Market risk may be magnified if certain social, political, economic, and other conditions and events (such as terrorism, conflicts, social unrest, natural disasters, epidemics and pandemics, including COVID-19) adversely interrupt the global economy and financial markets.

Growth Securities Risk. The Fund invests in companies that the portfolio managers believe have growth potential. Securities of companies perceived to be “growth” companies may be more volatile than other stocks and may involve special risks. If the portfolio managers’ perception of a company’s growth potential is not realized, the securities purchased may not perform as expected, reducing the Fund’s returns. In addition, because different types of stocks tend to shift in and out of favor depending on market and economic conditions, “growth” stocks may perform differently from the market as a whole and other types of securities.

Dividend-Oriented Stocks Risk. Companies that have paid regular dividends to shareholders may decrease or eliminate dividend payments in the future. A decrease in dividend payments by an issuer may result in a decrease in the value of the security held by the Fund or the Fund receiving less income.

Fixed-Income Securities Risk. The Fund holds debt and other fixed-income securities. A fundamental risk of fixed-income securities is interest rate risk, which is the risk that prices of bonds and other fixed-income securities will increase as interest rates fall and decrease as interest rates rise. The Fund may be subject to a greater risk of rising interest rates due to the current period of historically low rates. How specific fixed-income securities may react to changes in interest rates will depend on the specific characteristics of each security. For example, while securities with longer maturities and durations tend to offer higher yields, they also tend to be more sensitive to changes in prevailing interest rates and are therefore more volatile than shorter-term securities and are subject to greater market fluctuations as a result of changes in interest rates. Fixed-income securities are also subject to credit risk, prepayment risk, extension risk, valuation risk, and liquidity risk.

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Credit risk is the risk that the credit strength of an issuer of a fixed-income security will weaken and/or that the issuer will be unable to make timely principal and interest payments and that the security may go into default.

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Prepayment risk is the risk that, during periods of falling interest rates, certain debt obligations may be paid off quicker than originally anticipated, which may cause the Fund to reinvest its assets in securities with lower yields, resulting in a decline in the Fund’s income or return potential.

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Extension risk is the risk that, during periods of rising interest rates, certain debt obligations may be paid off substantially slower than originally anticipated, and the value of those securities may fall, resulting in a decline in the Fund’s income and potentially in the value of the Fund’s investments.

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Valuation risk is the risk that one or more of the fixed-income securities in which the Fund invests are priced differently than the value realized upon such security’s sale. In times of market instability, valuation may be more difficult.

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Liquidity risk is the risk that fixed-income securities may be difficult or impossible to sell at the time that the portfolio managers would like or at the price the portfolio managers believe the security is currently worth.

High-Yield/High-Risk Bond Risk. High-yield/high-risk bonds are considered speculative and may be more sensitive than other types of bonds to economic changes, political changes, or adverse developments specific to the company that issued the bond, which may adversely affect their value.

Portfolio Management Risk. The Fund is an actively managed investment portfolio and is therefore subject to the risk that the investment strategies employed for the Fund may fail to produce the intended results. The Fund may underperform its benchmark index or other mutual funds with similar investment objectives.

Mortgage- and Asset-Backed Securities Risk. Mortgage- and asset-backed securities represent interests in “pools” of commercial or residential mortgages or other assets, including consumer loans or receivables. Mortgage- and asset-backed securities may be more sensitive to changes in interest rates than other types of debt securities. Investments in mortgage-and asset-backed securities may be subject to both extension risk and prepayment risk. These risks may reduce the Fund’s returns. In addition, investments in certain mortgage- and asset-backed securities, including those comprised of subprime mortgages, may be subject to a higher degree of credit risk, valuation risk, and liquidity risk than various other types of fixed-income securities.

Loan Risk. The Fund may invest in a variety of loans. Bank loans are obligations of companies or other entities sometimes entered into in connection with recapitalizations, acquisitions, and refinancings. The Fund’s investments in bank loans are generally acquired as a participation interest in, or assignment of, loans originated by a lender or other financial institution. These investments may include institutionally-traded floating and fixed-rate debt securities. The bank loans underlying these securities often involve borrowers with low credit ratings whose financial conditions are troubled or uncertain, including companies that are highly leveraged. Loans are subject to credit risk, interest rate risk, and liquidity risk.

Sovereign Debt Risk. The Fund may invest in U.S. and non-U.S. government debt securities (“sovereign debt”). Some investments in sovereign debt, such as U.S. sovereign debt, are considered low risk. However, investments in sovereign debt, especially the debt of certain emerging market countries, can involve a high degree of risk, including the risk that the governmental entity that controls the repayment of sovereign debt may not be willing or able to repay the principal and/or to pay the interest on its sovereign debt in a timely manner. A sovereign debtor’s willingness or ability to satisfy its debt obligation may be affected by various factors including, but not limited to, its cash flow situation, the extent of its foreign currency reserves, the availability of foreign exchange when a payment is due, and the relative size of its debt position in relation to its economy as a whole. In the event of default, there may be limited or no legal remedies for collecting sovereign debt and there may be no bankruptcy proceedings through which the Fund may collect all or part of the sovereign debt that a governmental entity has not repaid. In addition, to the extent the Fund invests in non-U.S. sovereign debt, it may be subject to currency risk.

Derivatives Risk. Derivatives can be volatile and involve risks in addition to the risks of the underlying referenced securities or asset. Gains or losses from a derivative investment can be substantially greater than the derivative’s original cost, and can therefore involve leverage. Leverage may cause the Fund to be more volatile than if it had not used leverage. Derivatives can be less liquid than other types of investments and entail the risk that the counterparty will default on its payment obligations. The Fund may use derivatives for hedging purposes. While hedging can reduce or eliminate losses, it can also reduce or eliminate gains or cause losses if the market moves in a manner different from that anticipated by the portfolio managers or if the cost of the derivative outweighs the benefit of the hedge.

Liquidity Risk. The Fund may invest in securities or instruments that do not trade actively or in large volumes, and may make investments that are less liquid than other investments. Also, the Fund may make investments that may become less liquid in response to market developments or adverse investor perceptions. Investments that are illiquid or that trade in lower volumes may be more difficult to value. When there is no willing buyer and investments cannot be readily sold at the desired time or price, the Fund may have to accept a lower price or may not be able to sell the security or instrument at all. Investments in foreign securities, particularly those of issuers located in emerging market countries, tend to have greater exposure to liquidity risk than domestic securities. In unusual market conditions, even normally liquid securities may be affected by a degree of liquidity risk (i.e., if the number and capacity of traditional market participants is reduced). An inability to sell one or more portfolio positions can adversely affect the Fund’s value or prevent the Fund from being able to take advantage of other investment opportunities.

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Floating Rate Obligations Risk. The Fund may invest in floating rate obligations with interest rates that reset regularly, maintaining a fixed spread over a stated reference rate. The interest rates on floating rate obligations typically reset quarterly, although rates on some obligations may adjust at other intervals. Unexpected changes in the interest rates on floating rate obligations could result in lower income to the Fund. In addition, the secondary market on which floating rate obligations are traded may be less liquid than the market for investment grade securities or other types of income-producing securities, which may have an adverse impact on their market price. There is also a potential that there is no active market to trade floating rate obligations, that there may be restrictions on their transfer, or that the issuer may default. As a result, the Fund may be unable to sell floating rate obligations at the desired time or may be able to sell only at a price less than fair market value.

Foreign Exposure Risk. The Fund may have exposure to foreign markets as a result of its investments in foreign securities, including investments in emerging markets, which can be more volatile than the U.S. markets. As a result, its returns and net asset value may be affected by fluctuations in currency exchange rates or political or economic conditions in a particular country. In some foreign markets, there may not be protection against failure by other parties to complete transactions. It may not be possible for the Fund to repatriate capital, dividends, interest, and other income from a particular country or governmental entity. In addition, a market swing in one or more countries or regions where the Fund has invested a significant amount of its assets may have a greater effect on the Fund’s performance than it would in a more geographically diversified portfolio. To the extent the Fund invests in foreign debt securities, such investments are sensitive to changes in interest rates. Additionally, investments in securities of foreign governments involve the risk that a foreign government may not be willing or able to pay interest or repay principal when due. Some of the risks of investing directly in foreign securities may be reduced when the Fund invests indirectly in such securities through various other investment vehicles including derivatives, but such investments also involve other risks. The Fund’s investments in emerging market countries, if any, may involve risks greater than, or in addition to, the risks of investing in more developed countries.

TBA Commitments Risk. The Fund may enter into “to be announced” or “TBA” commitments. Although the particular TBA securities must meet industry-accepted “good delivery” standards, there can be no assurance that a security purchased on a forward commitment basis will ultimately be issued or delivered by the counterparty. If the counterparty to a transaction fails to deliver the securities, the Fund could suffer a loss. Because TBA commitments do not require the delivery of a specific security, the characteristics of a security delivered to the Fund may be less favorable than expected. There is a risk that the security that the Fund buys will lose value between the purchase and settlement dates. TBA purchase and sales commitments may significantly increase the Fund’s portfolio turnover rate and are not included in the portfolio turnover rate calculation.

Short Sales Risk. Short sales are speculative transactions and involve special risks, including a greater reliance on the ability to accurately anticipate the future value of a security. The Fund will suffer a loss if it sells a security short and the value of the security rises rather than falls. The Fund’s losses are potentially unlimited in a short sale transaction. The use of short sales may also cause the Fund to have higher expenses than those of other funds. In addition, due to the investment process of long and short positions, the Fund may be subject to additional transaction costs that may lower the Fund’s returns. The Fund’s use of short sales may also have a leveraging effect on the Fund’s portfolio and may increase losses and the volatility of returns.

Restricted Securities Risk. Securities that have limitations on their resale are referred to as “restricted securities.” Investments in restricted securities, including securities issued under Regulation S and Rule 144A, could have the effect of decreasing the Fund’s liquidity profile or preventing the Fund from disposing of them promptly at advantageous prices. Restricted securities may be less liquid than other investments because such securities may not always be readily sold in broad public markets and may have no active trading market. As a result, they may be difficult to value because market quotations may not be readily available.

LIBOR Replacement Risk. The Fund may invest in certain debt securities, derivatives, or other financial instruments that utilize the London Inter-Bank Offered Rate (“LIBOR”) as a reference rate for various rate calculations. The U.K. Financial Conduct Authority has announced that it intends to stop compelling or inducing banks to submit rates for many LIBOR settings after December 31, 2021, and for certain other commonly-used U.S. dollar LIBOR settings after June 30, 2023. The elimination of LIBOR or other reference rates and the transition process away from LIBOR could adversely impact (i) volatility and liquidity in markets that are tied to those reference rates, (ii) the market for, or value of, specific securities or payments linked to those reference rates, (iii) the availability or terms of borrowing or refinancing, or (iv) the effectiveness of hedging strategies. For these and other reasons, the elimination of LIBOR or other reference rates may adversely affect the Fund’s

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performance and/or net asset value. Alternatives to LIBOR are established or in development in most major currencies including the Secured Overnight Financing Rate (“SOFR”) that is intended to replace the U.S. dollar LIBOR.

The effect of the discontinuation of LIBOR or other reference rates on the Fund will vary depending on, among other things (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. Accordingly, it is difficult to predict the full impact of the transition away from LIBOR or other reference rates on the Fund until new reference rates and fallbacks for both legacy and new products, instruments and contracts are commercially accepted.

Securities Lending Risk. The Fund may seek to earn additional income through lending its securities to certain qualified broker-dealers and institutions. There is the risk that when portfolio securities are lent, the securities may not be returned on a timely basis, and the Fund may experience delays and costs in recovering the security or gaining access to the collateral provided to the Fund to collateralize the loan. If the Fund is unable to recover a security on loan, the Fund may use the collateral to purchase replacement securities in the market. There is a risk that the value of the collateral could decrease below the cost of the replacement security by the time the replacement investment is made, resulting in a loss to the Fund.

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.

Performance information

The following information provides some indication of the risks of investing in the Fund by showing how the Fund’s performance has varied over time. Class T Shares (formerly named Class J Shares, the initial share class) of the Fund commenced operations with the Fund’s inception. Class A Shares, Class C Shares, Class S Shares, Class I Shares, and Class R Shares of the Fund commenced operations on July 6, 2009. Class N Shares of the Fund commenced operations on May 31, 2012.

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The performance shown for Class T Shares is calculated using the fees and expenses of Class T Shares in effect during the periods shown, net of any applicable fee and expense limitations or waivers.

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The performance shown for Class A Shares, Class C Shares, Class S Shares, and Class R Shares for periods prior to July 6, 2009, reflects the performance of the Fund’s former Class J Shares, calculated using the fees and expenses of each respective share class, without the effect of any fee and expense limitations or waivers.

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The performance shown for Class I Shares for periods prior to July 6, 2009, reflects the performance of the Fund’s former Class J Shares, calculated using the fees and expenses of Class J Shares, net of any applicable fee and expense limitations or waivers.

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The performance shown for Class N Shares for periods prior to May 31, 2012, reflects the performance of the Fund’s Class T Shares, calculated using the fees and expenses of Class T Shares, net of any applicable fee and expense limitations or waivers.

If Class A Shares, Class C Shares, Class S Shares, Class I Shares, and Class R Shares of the Fund had been available during periods prior to July 6, 2009, or Class N Shares of the Fund had been available during periods prior to May 31, 2012, the performance shown for each respective share class may have been different. The performance shown for the periods following the Fund’s commencement of Class A Shares, Class C Shares, Class S Shares, Class I Shares, Class N Shares, and Class R Shares reflects the fees and expenses of each respective share class, net of any applicable fee and expense limitations or waivers.

The bar chart depicts the change in performance from year to year during the periods indicated. The bar chart figures do not include any applicable sales charges that an investor may pay when they buy or sell Class A Shares or Class C Shares of the Fund. If sales charges were included, the returns would be lower. The table compares the Fund’s average annual returns for the periods indicated to a broad-based securities market index, as well as to one or more supplemental indices that have investment characteristics similar to those of the Fund. All figures assume reinvestment of dividends and distributions. For certain periods, the Fund’s performance reflects the effect of expense waivers. Without the effect of these expense waivers, the performance shown would have been lower.

The Fund’s past performance (before and after taxes) does not necessarily indicate how it will perform in the future. Updated performance information is available at janushenderson.com/performance or by calling 1-877-335-2687.

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Annual Total Returns for Class T Shares (calendar year-end)

Best Quarter:

2nd Quarter 2020

12.86%

Worst Quarter:

1st Quarter 2020

– 11.56%

Average Annual Total Returns (periods ended 12/31/21)
	1 Year	5 Years	10 Years	Since Inception (9/1/92)
Class T Shares
Return Before Taxes	17.04%	14.25%	11.58%	10.24%
Return After Taxes on Distributions	15.76%	12.99%	10.27%	8.81%
Return After Taxes on Distributions and Sale of Fund Shares	10.83%	11.09%	9.12%	8.27%
S&P 500® Index (reflects no deduction for expenses, fees, or taxes)	28.71%	18.47%	16.55%	10.84%
Bloomberg U.S. Aggregate Bond Index (reflects no deduction for expenses, fees, or taxes)	– 1.54%	3.57%	2.90%	5.20%
Balanced Index (reflects no deduction for expenses, fees, or taxes)	14.32%	11.87%	10.46%	8.57%
Class A Shares
Return Before Taxes(1)	10.22%	12.80%	10.80%	9.96%
S&P 500® Index (reflects no deduction for expenses, fees, or taxes)	28.71%	18.47%	16.55%	10.84%
Bloomberg U.S. Aggregate Bond Index (reflects no deduction for expenses, fees, or taxes)	– 1.54%	3.57%	2.90%	5.20%
Balanced Index (reflects no deduction for expenses, fees, or taxes)	14.32%	11.87%	10.46%	8.57%
Class C Shares
Return Before Taxes(2)	15.14%	13.35%	10.67%	9.49%
S&P 500® Index (reflects no deduction for expenses, fees, or taxes)	28.71%	18.47%	16.55%	10.84%
Bloomberg U.S. Aggregate Bond Index (reflects no deduction for expenses, fees, or taxes)	– 1.54%	3.57%	2.90%	5.20%
Balanced Index (reflects no deduction for expenses, fees, or taxes)	14.32%	11.87%	10.46%	8.57%

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Average Annual Total Returns (periods ended 12/31/21)
	1 Year	5 Years	10 Years	Since Inception (9/1/92)
Class S Shares
Return Before Taxes	16.75%	13.96%	11.30%	10.03%
S&P 500® Index (reflects no deduction for expenses, fees, or taxes)	28.71%	18.47%	16.55%	10.84%
Bloomberg U.S. Aggregate Bond Index (reflects no deduction for expenses, fees, or taxes)	– 1.54%	3.57%	2.90%	5.20%
Balanced Index (reflects no deduction for expenses, fees, or taxes)	14.32%	11.87%	10.46%	8.57%
Class I Shares
Return Before Taxes	17.24%	14.45%	11.76%	10.32%
S&P 500® Index (reflects no deduction for expenses, fees, or taxes)	28.71%	18.47%	16.55%	10.84%
Bloomberg U.S. Aggregate Bond Index (reflects no deduction for expenses, fees, or taxes)	– 1.54%	3.57%	2.90%	5.20%
Balanced Index (reflects no deduction for expenses, fees, or taxes)	14.32%	11.87%	10.46%	8.57%
Class N Shares
Return Before Taxes	17.32%	14.53%	11.84%	10.33%
S&P 500® Index (reflects no deduction for expenses, fees, or taxes)	28.71%	18.47%	16.55%	10.84%
Bloomberg U.S. Aggregate Bond Index (reflects no deduction for expenses, fees, or taxes)	– 1.54%	3.57%	2.90%	5.20%
Balanced Index (reflects no deduction for expenses, fees, or taxes)	14.32%	11.87%	10.46%	8.57%
Class R Shares
Return Before Taxes	16.46%	13.68%	11.02%	9.79%
S&P 500® Index (reflects no deduction for expenses, fees, or taxes)	28.71%	18.47%	16.55%	10.84%
Bloomberg U.S. Aggregate Bond Index (reflects no deduction for expenses, fees, or taxes)	– 1.54%	3.57%	2.90%	5.20%
Balanced Index (reflects no deduction for expenses, fees, or taxes)	14.32%	11.87%	10.46%	8.57%

(1)

Calculated assuming maximum permitted sales loads.

(2)

The one year return is calculated to include the contingent deferred sales charge.

The Fund’s primary benchmark index is the S&P 500 Index. The Fund also compares its performance to the Bloomberg U.S. Aggregate Bond Index and the Balanced Index. The indices are described below.

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The S&P 500 Index is a commonly recognized, market capitalization-weighted index of 500 widely held equity securities, designed to measure broad U.S. equity performance.

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The Bloomberg U.S. Aggregate Bond Index is made up of U.S. dollar-denominated, fixed-rate taxable bonds, including securities that are of investment grade quality or better.

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The Balanced Index is an internally-calculated, hypothetical combination of unmanaged indices that combines total returns from the S&P 500 Index (55%) and the Bloomberg U.S. Aggregate Bond Index (45%).

After-tax returns are calculated using distributions for the Fund’s Class T Shares (formerly named Class J Shares, the initial share class). After-tax returns are calculated using the historically highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on your individual tax situation and may differ

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from those shown in the preceding table. The after-tax return information shown above does not apply to Fund shares held through a tax-advantaged account, such as a 401(k) plan or an IRA.

After-tax returns are only shown for Class T Shares of the Fund. After-tax returns for the other classes of Shares will vary from those shown for Class T Shares due to varying sales charges (as applicable), fees, and expenses among the classes.

Management

Investment Adviser: Janus Henderson Investors US LLC

Portfolio Managers: Jeremiah Buckley, CFA, is Executive Vice President and Co-Portfolio Manager of the Fund, which he has co-managed since December 2015. Michael Keough is Executive Vice President and Co-Portfolio Manager of the Fund, which he has co-managed since December 2019. Greg Wilensky, CFA, is Executive Vice President and Co-Portfolio Manager of the Fund, which he has co-managed since February 2020.

Purchase and sale of Fund shares

Minimum Investment Requirements

Class A Shares, Class C Shares*, Class S Shares, Class R Shares, and Class T Shares
Non-retirement accounts	$2,500**
Certain tax-advantaged accounts or UGMA/UTMA accounts	$500
Class I Shares
Institutional investors (investing directly with the Fund)	$1,000,000
Through an intermediary institution
• non-retirement accounts	$†2,500
• certain tax-advantaged accounts or UGMA/UTMA accounts	$†500
Class N Shares
Retirement investors (investing through an adviser-assisted, employer-sponsored retirement plan)	None
Retail investors (investing through a financial intermediary omnibus account)	$2,500***
Institutional investors (investing directly with the Fund)	$1,000,000

†

Exceptions to these minimums may apply for certain tax-advantaged, tax-qualified and retirement plans, including health savings accounts, accounts held through certain wrap programs, and certain retail brokerage accounts.

The maximum purchase in Class C Shares is $500,000 for any single purchase.

Class A, Class C, Class S, and Class T shares held through certain supermarket and/or self-directed brokerage accounts, or through wrap programs, may not be subject to these minimums. Please contact your financial intermediary for more information. For Class R shareholders, there is no investment minimum for defined contribution plans. Investors in a defined contribution plan through a third party administrator should refer to their plan document or contact their plan administrator for additional information regarding account minimums.

***

Investors in certain tax-advantaged accounts or accounts held through certain wrap programs or bank trust platforms may not be subject to this minimum.

Purchases, exchanges, and redemptions can generally be made only through institutional channels, such as financial intermediaries and retirement platforms. Class I Shares may be purchased directly by certain institutional investors who established Class I Shares accounts before August 4, 2017. You should contact your financial intermediary or refer to your plan documents for information on how to invest in the Fund. Requests must be received in good order by the Fund or its agents (financial intermediary or plan sponsor, if applicable) prior to the close of the regular trading session of the New York Stock Exchange in order to receive that day’s net asset value. For additional information, refer to “Purchases,” “Exchanges,” and/or “Redemptions” in the Prospectus.

Tax information

The Fund’s distributions are taxable, and will be taxed as ordinary income or capital gains, unless you are investing through a tax-advantaged arrangement, such as a 401(k) plan or an individual retirement account (in which case you may be taxed upon withdrawal of your investment from such account).

9 | Janus Henderson Balanced Fund

[JANUS HENDERSON LOGO]

Janus Henderson Balanced Fund

Ticker:

JANBX

Class D Shares

Summary Prospectus dated January 28, 2022

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, reports to shareholders, and other information about the Fund online at janushenderson.com/reports. You can also get this information at no cost by calling a Janus Henderson representative at 1-800-525-3713 or by sending an email request to prospectusorder@janushenderson.com.

Investment Objective

Janus Henderson Balanced Fund seeks long-term capital growth, consistent with preservation of capital and balanced by current income.

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.

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)		Class D
Management Fees		0.55%
Other Expenses		0.15%
Total Annual Fund Operating Expenses		0.70%

EXAMPLE:

The 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 assumes that you invest $10,000 in the Fund for the time periods indicated, reinvest all dividends and distributions, and then redeem all of your Shares at the end of each period. The Example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

	1 Year	3 Years	5 Years	10 Years
Class D Shares	$ 72	$ 224	$ 390	$ 871

Principal investment strategies

1 | Janus Henderson Balanced Fund

are know as “restricted securities”). The Fund may also invest in foreign securities, which may include investments in emerging market securities.

Principal investment risks

2 | Janus Investment Fund

rates fall and decrease as interest rates rise. The Fund may be subject to a greater risk of rising interest rates due to the current period of historically low rates. How specific fixed-income securities may react to changes in interest rates will depend on the specific characteristics of each security. For example, while securities with longer maturities and durations tend to offer higher yields, they also tend to be more sensitive to changes in prevailing interest rates and are therefore more volatile than shorter-term securities and are subject to greater market fluctuations as a result of changes in interest rates. Fixed-income securities are also subject to credit risk, prepayment risk, extension risk, valuation risk, and liquidity risk.

•

3 | Janus Henderson Balanced Fund

therefore involve leverage. Leverage may cause the Fund to be more volatile than if it had not used leverage. Derivatives can be less liquid than other types of investments and entail the risk that the counterparty will default on its payment obligations. The Fund may use derivatives for hedging purposes. While hedging can reduce or eliminate losses, it can also reduce or eliminate gains or cause losses if the market moves in a manner different from that anticipated by the portfolio managers or if the cost of the derivative outweighs the benefit of the hedge.

4 | Janus Investment Fund

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.

Performance information

The following information provides some indication of the risks of investing in the Fund by showing how the Fund’s performance has varied over time. Class D Shares of the Fund commenced operations on February 16, 2010, as a result of the restructuring of Class J Shares, the predecessor share class. The performance shown for Class D Shares for periods prior to February 16, 2010, reflects the performance of the Fund’s former Class J Shares, calculated using the fees and expenses in effect during the periods shown, net of any applicable fee and expense limitations or waivers. If Class D Shares of the Fund had been available during periods prior to February 16, 2010, the performance shown may have been different. The performance shown for the periods following the Fund’s commencement of Class D Shares reflects the fees and expenses of Class D Shares, net of any applicable fee and expense limitations or waivers.

The bar chart depicts the change in performance from year to year during the periods indicated. The table compares the Fund’s average annual returns for the periods indicated to a broad-based securities market index, as well as to one or more supplemental indices that have investment characteristics similar to those of the Fund. All figures assume reinvestment of dividends and distributions. For certain periods, the Fund’s performance reflects the effect of expense waivers. Without the

effect of these expense waivers, the performance shown would have been lower.

5 | Janus Henderson Balanced Fund

Annual Total Returns for Class D Shares (calendar year-end)

Best Quarter:

2nd Quarter 2020

12.90%

Worst Quarter:

1st Quarter 2020

– 11.52%

Average Annual Total Returns (periods ended 12/31/21)
	1 Year	5 Years	10 Years	Since Inception (9/1/92)
Class D Shares
Return Before Taxes	17.19%	14.38%	11.69%	10.29%
Return After Taxes on Distributions	15.87%	13.08%	10.35%	8.84%
Return After Taxes on Distributions and Sale of Fund Shares	10.93%	11.18%	9.20%	8.30%
S&P 500® Index (reflects no deduction for expenses, fees, or taxes)	28.71%	18.47%	16.55%	10.84%
Bloomberg U.S. Aggregate Bond Index (reflects no deduction for expenses, fees, or taxes)	– 1.54%	3.57%	2.90%	5.20%
Balanced Index (reflects no deduction for expenses, fees, or taxes)	14.32%	11.87%	10.46%	8.57%

The Fund’s primary benchmark index is the S&P 500 Index. The Fund also compares its performance to the Bloomberg U.S. Aggregate Bond Index and the Balanced Index. The indices are described below.

•

The S&P 500 Index is a commonly recognized, market capitalization-weighted index of 500 widely held equity securities, designed to measure broad U.S. equity performance.

•

The Bloomberg U.S. Aggregate Bond Index is made up of U.S. dollar-denominated, fixed-rate taxable bonds, including securities that are of investment grade quality or better.

•

After-tax returns are calculated using distributions for the Fund’s Class D Shares for the periods following February 16, 2010; and for the Fund’s Class J Shares, the predecessor share class, for periods prior to February 16, 2010. If Class D Shares of the Fund had been available during these earlier periods, distributions may have been different and thus, after-tax returns may have been different from those shown. After-tax returns are calculated using the historically highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on your individual tax situation and may differ from those shown in the preceding table. The after-tax return information shown

above does not apply to Fund shares held through a tax-advantaged account, such as a 401(k) plan or an IRA.

6 | Janus Investment Fund

Management

Investment Adviser: Janus Henderson Investors US LLC

Purchase and sale of Fund shares

Minimum Investment Requirements
To open a new regular Fund account	$2,500
To open a new regular Fund account with an automatic investment program of $50 per month	$100
To open a new UGMA/UTMA account, Coverdell Education Savings Account, or a retirement Fund account
• without an automatic investment program	$1,000
• with an automatic investment program of $50 per month	$100
To add to any existing type of Fund account without an automatic investment program	$50

You may generally purchase, exchange, or redeem Fund Shares on any business day by written request, wire transfer, telephone, and in most cases, online at janushenderson.com/individual. You may conduct transactions by mail (Janus Henderson, P.O. Box 219109, Kansas City, MO 64121-9109), or by telephone at 1-800-525-3713. Purchase, exchange, or redemption requests must be received in good order by the Fund or its agents prior to the close of the regular trading session of the New York Stock Exchange in order to receive that day’s net asset value. For additional information, refer to “To Open an Account or Buy Shares,” “To Exchange Shares,” and/or “To Sell Shares” in the Prospectus.

Tax information

Payments to broker-dealers and other financial intermediaries

With respect to share classes not offered in this Prospectus, the Fund or its distributor (or its affiliates) pay select broker-dealer firms or other financial intermediaries for the sale of Fund shares and related services. These payments may create a conflict of interest by influencing a broker-dealer or other intermediary or a salesperson to recommend the Fund over another investment or to recommend one share class over another.

7 | Janus Henderson Balanced Fund