Summary Prospectus by Investment Company (Form 497K)

PRINCIPAL CAPITAL APPRECIATION FUND

Class

A

Inst.

R-3

R-5

Ticker Symbol(s)

CMNWX

PWCIX

PCAOX

PCAQX

Principal Funds, Inc. Summary Prospectus March 1, 2026

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, 2026, as may be amended or supplemented, are incorporated by reference into this Summary Prospectus.

Objective

The Fund seeks to provide long-term growth of capital.

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. 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 Class A Shares of Principal Funds, Inc. More information about these and other discounts is available from your financial intermediary and in "Choosing a Share Class and The Costs of Investing" beginning on page 398 of the Fund's Prospectus, Appendix B to the Prospectus titled "Intermediary-Specific Sales Charge Waivers and Reductions," and "Multiple Class Structure" beginning on page 69 of the Fund's Statement of Additional Information.

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

A

Inst.

R-3

R-5

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)

5.50%

None

None

None

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
			A			Inst.			R-3			R-5
Management Fees			0.41%			0.41%			0.41%			0.41%
Distribution and/or Service (12b-1) Fees			0.25%			N/A			0.25%			N/A
Other Expenses			0.07%			0.04%			0.33%			0.27%
Total Annual Fund Operating Expenses			0.73%			0.45%			0.99%			0.68%

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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 A			$620			$771			$934			$1,407
Institutional Class			46			144			252			567
Class R-3			101			315			547			1,213
Class R-5			69			218			379			847

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 55.8% of the average value of its portfolio.

Principal Investment Strategies

The Fund invests primarily in equity securities of U.S. companies with any market capitalization, but it has a greater exposure to large market capitalization companies than small or medium market capitalization companies. Although there is no restriction on the size of the companies in which the Fund invests, most of the Fund's investments typically include companies with a market capitalization over $10 billion at the time of purchase. Those managing the Fund's investments seek to invest in securities of businesses that they believe are trading at a discount to their private market value (i.e., the value of the business if it was sold), have a competitive advantage, and/or that have barriers to entry in their respective industries.

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.

Equity Securities Risk. A variety of factors can negatively impact the value of equity securities held by a fund, including a decline in the issuer's financial condition, unfavorable performance of the issuer's sector or industry, or changes in response to overall market and economic conditions. A fund's principal market segment(s) (such as market capitalization or style) may underperform other market segments or the equity markets as a whole.

•Smaller Companies Risk. Investments in smaller companies may involve greater risk and price volatility than investments in larger, more mature companies. Smaller companies may have limited product lines, markets, or financial resources; lack the competitive strength of larger companies; have less experienced managers; or depend on a few key employees. Their securities often are less widely held and trade less frequently and in lesser quantities, and their market prices often fluctuate more, than securities of larger companies.

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.

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/mutualfundperformance.

The bar chart shows the investment returns of the Fund's Class A shares for each full calendar year of operations for 10 years (or, if shorter, the life of the Fund). These annual returns do not reflect sales charges on Class A shares; if

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they did, results would be lower. 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			19.69		%
Lowest return for a quarter during the period of the bar chart above:			Q1 2020			(19.46)		%

Average Annual Total Returns

For the periods ended December 31, 2025

			1 Year			5 Years			10 Years
Class A Return Before Taxes			6.97%			12.42%			13.54%
Class A Return After Taxes on Distributions			4.90%			11.11%			11.17%
Class A Return After Taxes on Distributions and Sale of Fund Shares			5.58%			9.70%			10.33%
Institutional Class Return Before Taxes			13.53%			14.04%			14.57%
Class R-3 Return Before Taxes			12.92%			13.42%			13.93%
Class R-5 Return Before Taxes			13.26%			13.77%			14.28%
Russell 1000 Index (reflects no deduction for fees, expenses, or taxes)			17.37%			13.59%			14.59%

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 Class A shares only and would be different for the other share classes.

Investment Advisor and Portfolio Managers

Principal Global Investors, LLC

•Daniel R. Coleman (since 2010), Portfolio Manager

•Theodore Jayne (since 2015), Portfolio Manager

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Purchase and Sale of Fund Shares

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

Effective as of the close of the New York Stock Exchange on March 24, 2023, Class C shares will no longer be available for purchase except in limited circumstances. See Purchase of Fund Shares for more information.

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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