0000932101 pif:S000003854Member pif:CommonStockRiskMember 2026-02-28 2026-02-28 0000932101 pif:S000003854Member pif:LargeShareholderTransactionRiskMember 2026-02-28 2026-02-28 0000932101 pif:S000003854Member pif:ManagementAndOperationalRiskMember 2026-02-28 2026-02-28 0000932101 pif:S000003854Member pif:MarketRisksMember 2026-02-28 2026-02-28 0000932101 pif:S000003854Member oef:RiskLoseMoneyMember 2026-02-28 2026-02-28 0000932101 pif:S000003854Member oef:RiskNotInsuredMember 2026-02-28 2026-02-28 0000932101 2026-02-28 2026-02-28 0000932101 pif:C000010787Member 2021-01-01 2025-12-31 0000932101 pif:C000010787Member oef:AfterTaxesOnDistributionsAndSalesMember 2021-01-01 2025-12-31 0000932101 pif:C000010787Member oef:AfterTaxesOnDistributionsMember 2021-01-01 2025-12-31 0000932101 pif:C000010789Member 2021-01-01 2025-12-31 0000932101 pif:C000010791Member 2021-01-01 2025-12-31 0000932101 pif:C000049250Member 2021-01-01 2025-12-31 0000932101 pif:C000135941Member 2021-01-01 2025-12-31 0000932101 pif:Russell2000ValueIndexMember 2021-01-01 2025-12-31 0000932101 pif:Russell3000IndexMember 2021-01-01 2025-12-31 0000932101 pif:S000003854Member pif:C000010787Member 2016-01-01 2016-12-31 0000932101 pif:S000003854Member pif:C000010787Member 2017-01-01 2017-12-31 0000932101 pif:S000003854Member pif:C000010787Member 2018-01-01 2018-12-31 0000932101 pif:S000003854Member pif:C000010787Member 2019-01-01 2019-12-31 0000932101 pif:S000003854Member pif:C000010787Member 2020-01-01 2020-12-31 0000932101 pif:S000003854Member pif:C000010787Member 2021-01-01 2021-12-31 0000932101 pif:S000003854Member pif:C000010787Member 2022-01-01 2022-12-31 0000932101 pif:S000003854Member pif:C000010787Member 2023-01-01 2023-12-31 0000932101 pif:S000003854Member pif:C000010787Member 2024-01-01 2024-12-31 0000932101 pif:C000010787Member 2025-01-01 2025-12-31 0000932101 pif:C000010787Member oef:AfterTaxesOnDistributionsAndSalesMember 2025-01-01 2025-12-31 0000932101 pif:C000010787Member oef:AfterTaxesOnDistributionsMember 2025-01-01 2025-12-31 0000932101 pif:C000010789Member 2025-01-01 2025-12-31 0000932101 pif:C000010791Member 2025-01-01 2025-12-31 0000932101 pif:C000049250Member 2025-01-01 2025-12-31 0000932101 pif:C000135941Member 2025-01-01 2025-12-31 0000932101 pif:Russell2000ValueIndexMember 2025-01-01 2025-12-31 0000932101 pif:Russell3000IndexMember 2025-01-01 2025-12-31 0000932101 pif:S000003854Member pif:C000010787Member 2025-01-01 2025-12-31 0000932101 pif:S000003854Member 2026-02-28 2026-02-28 0000932101 pif:S000003854Member pif:C000010787Member 2026-02-28 2026-02-28 0000932101 pif:S000003854Member pif:C000010789Member 2026-02-28 2026-02-28 0000932101 pif:S000003854Member pif:C000010791Member 2026-02-28 2026-02-28 0000932101 pif:S000003854Member pif:C000049250Member 2026-02-28 2026-02-28 0000932101 pif:S000003854Member pif:C000135941Member 2026-02-28 2026-02-28 0000932101 pif:C000010787Member 2016-01-01 2025-12-31 0000932101 pif:C000010787Member oef:AfterTaxesOnDistributionsAndSalesMember 2016-01-01 2025-12-31 0000932101 pif:C000010787Member oef:AfterTaxesOnDistributionsMember 2016-01-01 2025-12-31 0000932101 pif:C000010789Member 2016-01-01 2025-12-31 0000932101 pif:C000010791Member 2016-01-01 2025-12-31 0000932101 pif:C000049250Member 2016-01-01 2025-12-31 0000932101 pif:C000135941Member 2016-01-01 2025-12-31 0000932101 pif:Russell2000ValueIndexMember 2016-01-01 2025-12-31 0000932101 pif:Russell3000IndexMember 2016-01-01 2025-12-31 iso4217:USD pure 0000932101 false 485BPOS 2026-02-28 0.2659 0.0524 0.0791 -0.1981 0.2392 0.0357 0.3950 -0.1335 0.2355 0.0624 N-1A PUTNAM INVESTMENT FUNDS 2026-07-01 Fund summary Goal <div style="margin-top:2pt;margin-bottom:0pt;margin-left:2%;font-size:9pt;font-family:arial;">The fund seeks capital appreciation. </div> Fees and expenses <div style="margin-top:2pt;margin-bottom:0pt;margin-left:2%;font-size:9pt;font-family:arial;">The following tables describe the fees and expenses you may pay if you buy, hold and sell shares of the fund. <span style="font-weight:bold">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.</span> 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 <span style="font-style:italic">How do I buy fund shares?</span> beginning on page 17 of the fund’s prospectus, in the Appendix to the fund’s prospectus, and in <span style="font-style:italic">How to buy shares</span> beginning on page 17 of the fund’s Statement of Additional Information (“SAI”). </div> 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. 50000 Shareholder Fees (fees paid directly from your investment) 0.0575 0.0100 0 0.0100 0 0 0 0 0 0 Annual Fund Operating Expenses(expenses you pay each year as a percentage of the value of your investment) 0.0060 0.0025 0.0025 0.0110 0.0060 0.0100 0.0025 0.0185 0.0060 0.0050 0.0025 0.0135 0.0060 0 0.0013 0.0073 0.0060 0 0.0025 0.0085 Example <div style="margin-top:2pt;margin-bottom:0pt;margin-left:2%;font-size:9pt;font-family:arial;">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 </div><div style="margin-top:0pt;margin-bottom:0pt;margin-left:2%;font-size:9pt;font-family:arial;">5% return on your investment each year and that the fund’s operating expenses remain the same (except that any applicable fee waiver or expense reimbursement is reflected only through its expiration date). Your actual costs may be higher or lower. </div> 681 905 1147 1839 288 582 1001 1972 188 582 1001 1972 137 427 739 1623 75 234 407 908 87 271 471 1048 Portfolio turnover <div style="margin-top:2pt;margin-bottom:0pt;margin-left:2%;font-size:9pt;font-family:arial;">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 100%. </div> 1 Investments, risks, and performance Investments <div style="margin-top:2pt;margin-bottom:0pt;margin-left:2%;font-size:9pt;font-family:arial;">The fund invests mainly in common stocks of small U.S. companies, with a focus on value stocks. Under normal circumstances, the fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in equity securities of value companies of a size similar to those in the Russell 2000 Index over the past six months. This policy may be changed only after 60 days’ notice to shareholders. As of April 30, 2026, the index was composed of companies having market capitalizations of between approximately $18.3 million and $80.5 billion. The Investment Manager, as defined below, considers an issuer to be a value company if (i) the issuer is included in an index which is representative of value companies, (ii) the issuer is classified as a value company by an independent third party, and/or (iii) the Investment Manager believes the issuer is currently undervalued by the market. When assessing value companies, the Investment Manager considers a variety of factors, including, but not limited to financial metrics characteristic of value companies, such as low price-to-earnings ratios, low price-to-book ratios, low enterprise value to earnings before income tax, depreciation and amortization (EBITDA) ratios, low enterprise value to sales ratios and/or low enterprise to cash-flow ratios relative to the overall market or to a sector of the market. </div> <div style="margin-top:2pt;margin-bottom:0pt;margin-left:2%;font-size:9pt;font-family:arial;">The fund invests mainly in common stocks of small U.S. companies, with a focus on value stocks. Under normal circumstances, the fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in equity securities of value companies of a size similar to those in the Russell 2000 Index over the past six months. This policy may be changed only after 60 days’ notice to shareholders. As of April 30, 2026, the index was composed of companies having market capitalizations of between approximately $18.3 million and $80.5 billion. The Investment Manager, as defined below, considers an issuer to be a value company if (i) the issuer is included in an index which is representative of value companies, (ii) the issuer is classified as a value company by an independent third party, and/or (iii) the Investment Manager believes the issuer is currently undervalued by the market. When assessing value companies, the Investment Manager considers a variety of factors, including, but not limited to financial metrics characteristic of value companies, such as low price-to-earnings ratios, low price-to-book ratios, low enterprise value to earnings before income tax, depreciation and amortization (EBITDA) ratios, low enterprise value to sales ratios and/or low enterprise to cash-flow ratios relative to the overall market or to a sector of the market. </div><div style="margin-top:8pt;margin-bottom:0pt;margin-left:2%;font-size:9pt;font-family:arial;">The Investment Manager may consider, among other factors, a company’s valuation, financial strength, growth potential, competitive position in its </div><div style="margin-top:0pt;margin-bottom:0pt;margin-left:2%;font-size:9pt;font-family:arial;">industry, projected future earnings, cash flows and dividends when deciding whether to buy or sell investments. </div> Under normal circumstances, the fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in equity securities of value companies of a size similar to those in the Russell 2000 Index over the past six months. This policy may be changed only after 60 days’ notice to shareholders. <div style="margin-top:8pt;margin-bottom:0pt;margin-left:2%;font-size:9pt;font-family:arial;">The Investment Manager may consider, among other factors, a company’s valuation, financial strength, growth potential, competitive position in its </div><div style="margin-top:0pt;margin-bottom:0pt;margin-left:2%;font-size:9pt;font-family:arial;">industry, projected future earnings, cash flows and dividends when deciding whether to buy or sell investments. </div> It is important to understand that you can lose money by investing in the fund. <div style="margin-top:8pt;margin-bottom:0pt;margin-left:2%;font-size:9pt;font-family:arial;"><span style="font-weight:bold">Market risk:</span> 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, asset class, 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. </div> <div style="margin-top:8pt;margin-bottom:0pt;margin-left:2%;font-size:9pt;font-family:arial;"><span style="font-weight:bold">Common stock risk:</span> Common stock represents an ownership interest in a company. The value of a company’s stock may fall or fail to rise as a result of factors directly relating to that company, such as decisions made by its management or lower demand for the company’s products or services. A stock’s value may also fall because of factors affecting not just the company, but also other companies in the same industry or in a number of different industries, such as increases in production costs. Companies whose stocks the Investment Manager believes 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. Value stocks may fail to rebound, and the market may not favor value-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. </div> <div style="margin-top:8pt;margin-bottom:0pt;margin-left:2%;font-size:9pt;font-family:arial;"><span style="font-weight:bold">Large shareholder transaction risk:</span> The fund is subject to the risk that shareholders will purchase or redeem large quantities of shares of the fund. The fund may be an investment option for mutual funds that are managed by the Investment Manager, as defined below, 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. In addition, a large number of shareholders may collectively purchase or redeem fund shares in large amounts rapidly or unexpectedly. Large shareholder transactions may adversely affect the fund’s liquidity and net assets. These redemptions may also adversely affect the fund’s performance if the fund is forced to sell securities, which may also increase the fund’s brokerage costs. </div> <div style="margin-top:8pt;margin-bottom:0pt;margin-left:2%;font-size:9pt;font-family:arial;"><span style="font-weight:bold">Management and operational risk:</span> There is no guarantee that the investment techniques, analyses, or judgments that the Investment Manager applies in making investment decisions for the fund will produce the intended outcome or that the investments selected for the fund will perform as well as other </div><div style="margin-top:0pt;margin-bottom:0pt;margin-left:2%;font-size:9pt;font-family:arial;">securities that were not selected for the fund. The Investment Manager, or the fund’s other service providers, may experience disruptions or operating errors that could negatively impact the fund. </div> An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Performance <div style="margin-top:12pt;margin-bottom:0pt;margin-left:2%;font-size:9pt;font-family:arial;">The accompanying bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Class A shares. The table shows the average annual total returns of each class of the fund that has been in operation for at least one full calendar year and also compares the fund’s performance with the average annual total returns of a broad measure of market performance and an additional index with characteristics relevant to the fund. Performance for classes other than those shown may vary from the performance shown to the extent the expenses for those classes differ. The fund makes updated performance information, including its current net asset value per share, available at www.franklintempleton.com. </div><div style="margin-top:8pt;margin-bottom:0pt;margin-left:2%;font-size:9pt;font-family:arial;text-align:justify;"><span style="font-style:italic">The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. </span></div><div style="margin-top:8pt;margin-bottom:0pt;margin-left:2%;font-size:9pt;font-family:arial;">Sales charges are not reflected in the accompanying bar chart, and if those charges were included, returns would be less than those shown. </div> The bar chart shows changes in the fund’s performance from year to year for Class A shares. The table shows the average annual total returns of each class of the fund that has been in operation for at least one full calendar year and also compares the fund’s performance with the average annual total returns of a broad measure of market performance and an additional index with characteristics relevant to the fund. www.franklintempleton.com The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Sales charges are not reflected in the accompanying bar chart, and if those charges were included, returns would be less than those shown. Annual total returns for class A shares before sales charges <table cellpadding="0" cellspacing="0" style="border-collapse:collapse;font-family:arial narrow;font-size:8pt;width:98%;border-spacing:0px;margin-left:auto"> <tr> <td style="width:26%;"></td> <td style="vertical-align:bottom;width:1%;"></td> <td style="width:64%;"></td> <td style="vertical-align:bottom;width:2%;"></td> <td style="width:4%;"></td> </tr> <tr style="page-break-inside:avoid;font-family:arial narrow;font-size:8pt;background-color:#cceeff"> <td style="BORDER-TOP:0.75pt solid #b2b2b2; BORDER-BOTTOM:0.75pt solid #b2b2b2;vertical-align:top;">Best Quarter:</td> <td style=" BORDER-TOP:0.75pt solid #b2b2b2; BORDER-BOTTOM:0.75pt solid #b2b2b2;vertical-align:bottom;">  </td> <td style="BORDER-TOP:0.75pt solid #b2b2b2; BORDER-BOTTOM:0.75pt solid #b2b2b2;vertical-align:bottom;text-align:center;">Q4 2020</td> <td style=" BORDER-TOP:0.75pt solid #b2b2b2; BORDER-BOTTOM:0.75pt solid #b2b2b2;vertical-align:bottom;">  </td> <td style="BORDER-TOP:0.75pt solid #b2b2b2; BORDER-BOTTOM:0.75pt solid #b2b2b2;vertical-align:bottom;text-align:center;">34.11%</td> </tr> <tr style="page-break-inside:avoid;font-family:arial narrow;font-size:8pt"> <td style="BORDER-BOTTOM:0.75pt solid #b2b2b2;vertical-align:top;">Worst Quarter:</td> <td style=" BORDER-BOTTOM:0.75pt solid #b2b2b2;vertical-align:bottom;">  </td> <td style="BORDER-BOTTOM:0.75pt solid #b2b2b2;vertical-align:bottom;text-align:center;">Q1 2020</td> <td style=" BORDER-BOTTOM:0.75pt solid #b2b2b2;vertical-align:bottom;">  </td> <td style="BORDER-BOTTOM:0.75pt solid #b2b2b2;vertical-align:bottom;text-align:center;">-40.59%</td> </tr> <tr style="page-break-inside:avoid;font-family:arial narrow;font-size:8pt;background-color:#cceeff"> <td colspan="5" style="BORDER-BOTTOM:0.75pt solid #b2b2b2;vertical-align:top;">As of March 31, 2026, the fund’s year-to-date return was 1.42%.</td> </tr> </table> Best Quarter: 2020-12-31 0.3411 Worst Quarter: 2020-03-31 -0.4059 2026-03-31 year-to-date return 0.0142 Average annual total returns after sales charges(for periods ended 12/31/25) -0.0081 0.0949 0.0826 -0.0240 0.0834 0.0607 0.0050 0.0735 0.0584 0.0356 0.1000 0.0826 0.0496 0.1052 0.0864 0.0563 0.1123 0.0935 0.0550 0.1108 0.0918 0.1715 0.1315 0.1429 0.1259 0.0888 0.0927 <div style="margin-top:18pt;margin-bottom:0pt;margin-left:2%;font-size:9pt;font-family:arial;">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. </div><div style="margin-top:8pt;margin-bottom:0pt;margin-left:2%;font-size:9pt;font-family:arial;">Class C share performance reflects conversion to class A shares after eight years. </div><div style="margin-top:8pt;margin-bottom:0pt;margin-left:2%;font-size:9pt;font-family:arial;">Important data provider notices and terms are available at <span style="font-family:arial;font-size:9pt;color:#467886"><span style="text-decoration:underline">www.franklintempletondatasources.com</span></span><span style="font-family:arial">. Such information is subject to change. </span></div> 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. 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.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. Applies only to certain redemptions of shares bought with no initial sales charge. This charge is eliminated after one year.