Summary Prospectus by Investment Company - Form 497K

Putnam
Small Cap Growth
Fund

Summary prospectus

10 | 30 | 24

FUND SYMBOLS	CLASS A	CLASS C	CLASS R	CLASS R6	CLASS Y
	PNSAX	PNSCX	PSGRX	PLKGX	PSYGX

Putnam Small Cap Growth Fund

Before you invest, you may wish to review the fund's prospectus, which contains more information about the fund and its risks. You may obtain the prospectus and other information about the fund, including the statement of additional information ("SAI") and most recent reports to shareholders, at no cost by visiting www.franklintempleton.com or calling Putnam Investor Services at 1-800-225-1581.

The fund's prospectus and SAI, both dated 10/30/24, are incorporated by reference into this summary prospectus.

Goal

Putnam Small Cap Growth Fund seeks capital appreciation.

Fees and expenses

The following tables describe the fees and expenses you may pay if you buy, hold and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. 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 Putnam funds. More information about these and other discounts is available from your financial professional and in How do I buy fund shares? beginning on page 15 of the fund's prospectus, in the Appendix to the fund's prospectus, and in How to buy shares beginning on page II-1 of the fund's statement of additional information ("SAI").

Shareholder fees (fees paid directly from your investment)

Share class	Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	Maximum deferred sales charge (load) (as a percentage of original purchase price or redemption proceeds, whichever is lower)
Class A	5.75%	1.00%*
Class C	NONE	1.00%**
Class R	NONE	NONE
Class R6	NONE	NONE
Class Y	NONE	NONE

2

Annual fund operating expenses
(expenses you pay each year as a percentage of the value of your investment)

Share class	Management fees†	Distribution and service (12b-1) fees	Other expenses	Total annual fund operating expenses
Class A	0.70%	0.25%	0.26%	1.21%
Class C	0.70%	1.00%	0.26%	1.96%
Class R	0.70%	0.50%	0.26%	1.46%
Class R6	0.70%	N/A	0.11%	0.81%
Class Y	0.70%	N/A	0.26%	0.96%

*	Applies only to certain redemptions of shares bought with no initial sales charge.

**	This charge is eliminated after one year.

†

Management fees are subject to a performance adjustment. The fund's base management fee is subject to adjustment, up or down, based on the fund's performance relative to the performance of the Russell 2000 Growth Index. For the most recent fiscal year, the fund's base management fee prior to any performance adjustment was 0.616%.

Example

The following hypothetical example is intended to help you compare the cost of investing in the fund with the cost of investing in other funds. It assumes that you invest $10,000 in the fund for the time periods indicated and then, except as indicated, redeem all your shares at the end of those periods. It assumes a 5% return on your investment each year and that the fund's operating expenses remain the same. Your actual costs may be higher or lower.

Share class	1 year	3 years	5 years	10 years
Class A	$691	$937	$1,202	$1,957
Class C	$299	$615	$1,057	$2,091
Class C (no redemption)	$199	$615	$1,057	$2,091
Class R	$149	$462	$797	$1,746
Class R6	$83	$259	$450	$1,002
Class Y	$98	$306	$531	$1,178

Portfolio turnover

The fund pays transaction-related costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher turnover rate may indicate higher transaction costs and may result in higher taxes when the fund's shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or the above example, affect fund performance. The fund's turnover rate in the most recent fiscal year was 40%.

3

Investments, risks, and performance

Investments

We invest mainly in common stocks of small U.S. companies, with a focus on growth stocks. Growth stocks are issued by companies whose earnings are expected to grow faster than those of similar firms, and whose business growth and other characteristics may lead to an increase in stock price. Under normal circumstances, we invest at least 80% of the fund's net assets in companies of a size similar to those in the Russell 2000 Growth Index. This policy may be changed only after 60 days' notice to shareholders. As of August 31, 2024, the index was composed of companies having market capitalizations of between approximately $11.8 million and $13.1 billion.

We may consider, among other factors, a company's valuation, financial strength, growth potential, competitive position in its industry, projected future earnings, cash flows and dividends when deciding whether to buy or sell investments.

Risks

It is important to understand that you can lose money by investing in the fund.

The value of investments in the fund's portfolio may fall or fail to rise over extended periods of time for a variety of reasons, including general economic, political or financial market conditions, investor sentiment and market perceptions, government actions, geopolitical events or changes, outbreaks of infectious illnesses or other widespread public health issues, and factors related to a specific issuer, geography, industry or sector. These and other factors may lead to increased volatility and reduced liquidity in the fund's portfolio holdings, may negatively impact the fund's performance, and may exacerbate other risks to which the fund is subject. Companies whose stocks we believe are undervalued by the market may have experienced adverse business developments or may be subject to special risks that have caused their stocks to be out of favor. Growth stocks may be more susceptible to earnings disappointments, and the market may not favor growth-style investing. These risks are generally greater for small and midsize companies. From time to time, the fund may invest a significant portion of its assets in companies in one or more related industries or sectors, which would make the fund more vulnerable to adverse developments affecting those industries or sectors.

The fund may be an investment option for mutual funds that are managed by Franklin Resources, Inc. ("Franklin Templeton") and its affiliates as "funds of funds." Additionally, other investors from time to time may make substantial investments in the fund. Such shareholders may at times be considered to control the fund. Dispositions of a large number of shares by these shareholders may adversely affect the fund's liquidity and net assets. These redemptions may also force the fund to sell securities, which may increase the fund's brokerage costs.

There is no guarantee that the investment techniques, analyses, or judgments that we apply in making investment decisions for the fund will produce the intended outcome or that the investments we select for the fund will perform as well as other securities

4

that were not selected for the fund. We, or the fund's other service providers, may experience disruptions or operating errors that could negatively impact the fund.

The fund may not achieve its goal, and it is not intended to be a complete investment program. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

Performance

The performance information below gives some indication of the risks associated with an investment in the fund by showing the fund's performance year to year and over time. The bar chart does not reflect the impact of sales charges. If it did, performance would be lower. Please remember that past performance is not necessarily an indication of future results. Monthly performance figures for the fund are available at www.franklintempleton.com.

Annual total returns for class A shares before sales charges

Year-to-date performance through 9/30/24	26.37%
Best calendar quarter Q2 2020	32.31%
Worst calendar quarter Q4 2018	-20.71%

Average annual total returns after sales charges (for periods ended 12/31/23)

Share class	1 year	5 years	10 years
Class A before taxes	15.80%	14.07%	9.30%
Class A after taxes on distributions	15.80%	12.86%	8.67%
Class A after taxes on distributions and sale of fund shares	9.36%	11.23%	7.60%
Class C before taxes	20.96%	14.56%	9.28%
Class R before taxes	22.59%	15.13%	9.67%
Class R6 before taxes*	23.38%	15.88%	10.36%
Class Y before taxes	23.18%	15.71%	10.22%
Russell 3000 Index**,*** (no deduction for fees, expense or taxes)	25.96%	15.16%	11.48%
Russell 2000 Growth Index **,*** (no deduction for fees, expenses or taxes)	18.66%	9.22%	7.16%

*	Performance for class R6 shares prior to their inception (6/29/15) is derived from the historical performance of class Y shares and has not been adjusted for the lower investor servicing fees applicable to class R6 shares; had it been adjusted, returns would have been higher.

**	Frank Russell Company is the source and owner of the trademarks, service marks and copyrights related to the Russell Indexes. Russell ® is a trademark of Frank Russell Company.

5

***

The table above compares the fund's returns to the performance of two indexes: (i) the Russell 3000 Index, a broad measure of market performance, and (ii) the Russell 2000 Growth Index, an additional index that the Investment Manager believes more closely reflects the fund's principal investment objective and strategies.

After-tax returns reflect the historical highest individual federal marginal income tax rates and do not reflect state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are shown for class A shares only and will vary for other classes. These after-tax returns do not apply if you hold your fund shares through a 401(k) plan, an IRA, or another tax-advantaged arrangement.

Class C share performance reflects conversion to class A shares after eight years.

Your fund's management

Investment advisor

Putnam Investment Management, LLC ("Putnam Management" or the "Investment Manager")

Portfolio managers

William Monroe, CFA
Portfolio Manager, portfolio manager
of the fund since 2017

Tania Harsono, CFA
Portfolio Manager, portfolio manager
of the fund since 2024

Sub-advisors

Franklin Advisers, Inc. ("Franklin Advisers")

Putnam Investments Limited ("PIL")*

*	Though the Investment Manager has retained the services of PIL, PIL does not currently manage any assets of the fund.

The Investment Manager, Franklin Advisers and PIL are each direct or indirect, wholly-owned subsidiaries of Franklin Templeton.

Purchase and sale of fund shares

You can open an account, purchase and/or sell fund shares, or exchange them for shares of another Putnam fund by contacting your financial professional or by calling Putnam Investor Services at 1-800-225-1581.

When opening an account, you must complete and mail an account application, along with a check made payable to the fund, to: Putnam Investor Services, P.O. Box 219697, Kansas City, MO 64121-9697. The minimum initial investment of $500 is currently waived, although the fund reserves the right to reject initial investments under $500 at its discretion. There is no minimum for subsequent investments.

You can sell your shares back to the fund or exchange them for shares of another Putnam fund any day the New York Stock Exchange ("NYSE") is open. Shares may be sold or exchanged by mail, by phone, or, for exchanges only, online at www.franklintempleton.com. Some restrictions may apply.

6

Tax information

The fund's distributions will be taxed as ordinary income or capital gains unless you hold the shares through a tax-advantaged arrangement, in which case you will generally be taxed only upon withdrawal of monies from the arrangement.

Financial intermediary compensation

If you purchase the fund through a broker/dealer or other financial intermediary (such as a bank or financial professional), the fund and its related companies may pay that intermediary for the sale of fund shares and related services. Please bear in mind that these payments may create a conflict of interest by influencing the broker/dealer or other intermediary to recommend the fund over another investment. Ask your advisor or visit your advisor's website for more information.

Information about the Summary Prospectus, Prospectus, and SAI

The summary prospectus, prospectus, and SAI for a fund provide information concerning the fund. The summary prospectus, prospectus, and SAI are updated at least annually and any information provided in a summary prospectus, prospectus, or SAI can be changed without a shareholder vote unless specifically stated otherwise. The summary prospectus, prospectus, and the SAI are not contracts between the fund and its shareholders and do not give rise to any contractual rights or obligations or any shareholder rights other than any rights conferred explicitly by federal or state securities laws that may not be waived.

Additional information, including current performance, is available at www.franklintempleton.com or calling Putnam Investor Services at 1-800-225-1581.

7

38972-PSUM 10/24

Public link

Please use the above public link if you want to share this noodl on another website.