Summary Prospectus by Investment Company (Form 497K)

INFLATION PROTECTION FUND

Class

J

Inst.

R-3

R-5

Ticker Symbol(s)

PIPJX

PIPIX

PIFPX

PBPPX

Principal Funds, Inc. Summary Prospectus March 1, 2025 as amended September 17, 2025

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, Reports to Shareholders, and other information about the Fund online at www.PrincipalAM.com/Prospectuses. You can also get this information at no cost by calling 1-800-222-5852 or by sending an email request to [email protected].

The Fund's Prospectus and Statement of Additional Information, both dated March 1, 2025, as may be amended or supplemented, are incorporated by reference into this Summary Prospectus.

Objective

The Fund seeks to provide current income and real (after inflation) total returns.

Fees and Expenses of the Fund

This table describes the fees and expenses that 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.

If you purchase Institutional Class shares through certain programs offered by certain financial intermediaries, you may be required to pay a commission and/or other forms of compensation to the broker, or to your Financial Professional or other financial intermediary.

Shareholder Fees (fees paid directly from your investment)

Share Class

J

Inst.

R-3

R-5

Maximum Deferred Sales Charge (Load) (as a percentage of the offering price or NAV when Sales Load is paid, whichever is less)

1.00%

None

None

None

Annual Fund Operating Expenses

(expenses that you pay each year as a percentage of the value of your investment)

			Share Class
			J			Inst.			R-3			R-5
Management Fees			0.38 %			0.38 %			0.38 %			0.38 %
Distribution and/or Service (12b-1) Fees			0.15 %			N/A			0.25 %			N/A
Other Expenses			0.26 %			0.01 %			0.33 %			0.27 %
Total Annual Fund Operating Expenses			0.79 %			0.39 %			0.96 %			0.65 %

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Example

This 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 then redeem all of your shares at the end of those periods. 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 J			$181			$252			$439			$978
Institutional Class			40			125			219			493
Class R-3			98			306			531			1,178
Class R-5			66			208			362			810

With respect to Class J shares, you would pay the following expenses if you did not redeem your shares (all other classes would be the same as in the above example):

			1 year			3 years			5 years			10 years
Class J			$81			$252			$439			$978

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 109.6% of the average value of its portfolio.

Principal Investment Strategies

The Fund invests primarily in inflation-indexed bonds of varying maturities issued by the U.S. and non-U.S. governments, their agencies, or instrumentalities, and U.S. and non-U.S. corporations. Inflation-indexed bonds are fixed-income securities that are structured to provide protection against inflation. The value of the bond's principal or the interest income paid on the bond is adjusted to track changes in an official inflation measure. The U.S. Treasury uses the Consumer Price Index for Urban Consumers as the inflation measure. Inflation-indexed bonds issued by a foreign government are generally adjusted to reflect a comparable inflation index, calculated by that government. The Fund also invests in foreign securities, U.S. Treasuries, and agency securities. The Fund utilizes derivative strategies (specifically, futures, swaps, and options) for purposes of managing the risk profile of the Fund. A derivative is a financial arrangement, the value of which is derived from, or based on, a traditional security, asset, or market index.

Under normal circumstances, the Fund maintains an average portfolio duration that is within ±20% of the duration of the Bloomberg U.S. Treasury Inflation Protected Securities ("TIPS") Index, which as of January 31, 2025 was 6.60 years. The Fund is not managed to a particular maturity. The Fund's strategies may result in the active and frequent trading of the Fund's portfolio securities.

Principal Risks

The value of your investment in the Fund changes with the value of the Fund's investments. Many factors affect that value, and it is possible to lose money by investing in the Fund. An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The principal risks of investing in the Fund are listed below in alphabetical order and not in order of significance.

Counterparty Risk. Counterparty risk is the risk that the counterparty to a contract or other obligation will be unable or unwilling to honor its obligations.

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Derivatives Risk. Derivatives may not move in the direction anticipated by the portfolio manager. Transactions in derivatives may increase volatility, cause the liquidation of portfolio positions when not advantageous to do so, and result in disproportionate losses that may be substantially greater than a fund's initial investment.

•Futures and Swaps. These derivative instruments involve specific risks, including: the imperfect correlation between the change in market value of the instruments held by the fund and the price of the instruments; possible lack of a liquid secondary market for an instrument and the resulting inability to close it when desired; counterparty risk; and if the fund has insufficient cash, it may have to sell securities from its portfolio to meet any applicable daily variation margin requirements.

•Options. Options involve specific risks, including: the imperfect correlation between the change in market value of the instruments held by the Fund and the price of the options; counterparty risk; difference in trading hours for the options markets and the markets for the underlying securities (rate movements can take place in the underlying markets that cannot be reflected in the options markets); and an insufficient liquid secondary market for particular options.

Fixed-Income Securities Risk. Fixed-income securities are subject to interest rate, credit quality, and liquidity risks. The market value of fixed-income securities generally declines when interest rates rise, and increased interest rates may adversely affect the liquidity of certain fixed-income securities. Moreover, an issuer of fixed-income securities could default on its payment obligations due to increased interest rates or for other reasons.

Foreign Currency Risk. Risks of investing in securities denominated in, or that trade in, foreign (non-U.S.) currencies include changes in foreign exchange rates and foreign exchange restrictions.

Foreign Securities Risk. The risks of foreign securities include loss of value as a result of: political or economic instability; nationalization, expropriation, or confiscatory taxation; settlement delays; and limited government regulation (including less stringent reporting, accounting, and disclosure standards than are required of U.S. companies).

High Portfolio Turnover Risk. High portfolio turnover (more than 100%) caused by active and frequent trading of portfolio securities may result in accelerating the realization of taxable gains and losses, lower fund performance, and increased brokerage costs.

Portfolio Duration Risk. Portfolio duration is a measure of the expected life of a fixed-income security and its sensitivity to changes in interest rates. The longer a fund's average portfolio duration, the more sensitive the fund will be to changes in interest rates, which means funds with longer average portfolio durations may be more volatile than those with shorter durations.

Redemption and Large Transaction Risk. Ownership of the Fund's shares may be concentrated in one or a few large investors (such as funds of funds, institutional investors, and asset allocation programs) that may redeem or purchase shares in large quantities. These transactions may cause the Fund to sell securities to meet redemptions or to invest additional cash at times it would not otherwise do so, which may result in increased transaction costs, increased expenses, changes to expense ratios, and adverse effects to Fund performance. Such transactions may also accelerate the realization of taxable income if sales of portfolio securities result in gains. Moreover, reallocations by large shareholders among share classes of a fund may result in changes to the expense ratios of affected classes, which may increase the expenses paid by shareholders of the class that experienced the redemption.

U.S. Government Securities Risk. Yields available from U.S. government securities are generally lower than yields from many other fixed-income securities. The value of U.S. government securities may be adversely impacted by changes in interest rates, changes in the credit rating of the U.S. government, or a default by the U.S. government.

U.S. Government-Sponsored Securities Risk. Securities issued by U.S. government-sponsored enterprises such as the Federal Home Loan Mortgage Corporation, the Federal National Mortgage Association, and the Federal Home Loan Banks are not issued or guaranteed by the U.S. government.

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Performance

The following information provides some indication of the risks of investing in the Fund. Past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. You may get updated performance information at www.PrincipalAM.com.

The bar chart shows the investment returns of the Fund's Institutional Class shares for each full calendar year of operations for 10 years (or, if shorter, the life of the Fund). The table shows for the last one, five, and ten calendar year periods (or, if shorter, the life of the Fund), how the Fund's average annual total returns compare with those of one or more broad measures of market performance.

Total Returns as of December 31

Highest return for a quarter during the period of the bar chart above:			Q2 2020			4.72		%
Lowest return for a quarter during the period of the bar chart above:			Q2 2022			(6.33)		%

Average Annual Total Returns

For the periods ended December 31, 2024

			1 Year			5 Years			10 Years
Institutional Class Return Before Taxes			1.66%			1.51%			1.84%
Institutional Class Return After Taxes on Distributions			0.29%			(0.15)%			0.65%
Institutional Class Return After Taxes on Distributions and Sale of Fund Shares			0.98%			0.53%			0.93%
Class J Return Before Taxes			0.40%			1.09%			1.27%
Class R-3 Return Before Taxes			1.19%			0.95%			1.27%
Class R-5 Return Before Taxes			1.40%			1.27%			1.59%
Bloomberg U.S. Aggregate Bond Index (reflects no deduction for fees, expenses, or taxes)			1.25%			(0.33)%			1.35%
Bloomberg U.S. Treasury TIPS Index (reflects no deduction for fees, expenses, or taxes)			1.84%			1.87%			2.24%

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. The after-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Institutional Class shares only and would be different for the other share classes.

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The Bloomberg U.S. Aggregate Bond Index is the Fund's primary broad-based index and is included to meet the recently revised definition of "broad-based securities market index." The Bloomberg U.S. Treasury TIPS Index is included as an additional index for the Fund as it shows how the Fund's performance compares with the returns of an index of funds with similar investment objectives.

Investment Advisor

Principal Global Investors, LLC

Sub-Advisor and Portfolio Manager

BlackRock Financial Management, Inc.

•Harrison Segall (since 2024), Director

Sub-Sub-Advisor and Portfolio Manager

BlackRock International Limited

•Johan Sjogren (since 2024), Managing Director

Purchase and Sale of Fund Shares

Share Class			Investment Type			Purchase Minimum Per Fund
J			Initial Investment			$1,000(1)
J			Initial Investment for accounts with an Automatic Investment Plan (AIP)			$100
J			Subsequent Investments			$100(1)(2)
Institutional, R-3, and R-5			There are no minimum initial or subsequent investment requirements for eligible purchases.			N/A

(1)Some exceptions apply; see "Purchase of Fund Shares - Minimum Investments" for more information.

(2)For accounts with an AIP, the subsequent automatic investments must total $1,200 annually if the initial $1,000 minimum has not been met.

You may purchase or redeem shares on any business day (normally any day when the New York Stock Exchange is open for regular trading) through your plan, intermediary, or Financial Professional by sending a written request to Principal Funds at P.O. Box 219971, Kansas City, MO 64121-9971 (regular mail) or 801 Pennsylvania Ave., Ste. 219971, Kansas City, MO 64105-1307 (overnight mail); calling us at 1-800-222-5852; or accessing our website (www.principal.com).

Tax Information

The Fund's distributions you receive are generally subject to federal income tax as ordinary income or capital gain and may also be subject to state and local taxes, unless you are tax-exempt or your account is tax-deferred in which case your distributions would be taxed when withdrawn from the tax-deferred 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 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 salesperson to recommend the Fund over another investment, or to recommend one share class of the Fund over another share class. Ask your salesperson or visit your financial intermediary's website for more information.

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