A charitable foundation is a tax-exempt organization, recognized under Section 501(c)(3) of the Internal Revenue Code, that dedicates private wealth to a public purpose such as funding medical research, supporting education, or running a homeless shelter. Most foundations are private, meaning they draw their funding from a single individual, family, or corporation rather than from broad public support. That structure buys the founder control and a lasting charitable vehicle, but it also comes with strict federal rules on how the foundation earns income, pays out grants, and interacts with the people connected to it.
Private Foundation or Public Charity
The IRS treats every 501(c)(3) organization as a private foundation by default unless it proves it qualifies as a public charity. The line runs mainly through funding sources. A public charity must receive at least one-third of its support from the general public, government grants, or a combination of both, measured over a rolling five-year period.1Internal Revenue Service. Exempt Organizations Annual Reporting Requirements – Form 990, Schedules A and B: Public Charity Support Test Organizations that fall short can still qualify under a facts-and-circumstances test if they get at least 10% of their support from public sources and can show a broad fundraising program.2Internal Revenue Service. Publicly Supported Charities
The classification shapes both sides of the giving relationship. Donors to public charities get higher annual deduction limits. Private foundations, for their part, face a web of excise taxes and operational restrictions that public charities largely avoid.
Operating and Non-Operating Foundations
Within the private foundation world, the IRS draws a further line. An operating foundation runs its own charitable programs directly, such as a family that funds and manages a museum, a medical research lab, or a community health clinic. A non-operating foundation is primarily a checkbook: it manages an endowment and distributes grants to other charities. Most private foundations are non-operating, and they face a mandatory annual payout requirement that operating foundations can satisfy differently.
Forming a Foundation and Getting IRS Approval
Starting a foundation begins with incorporating, or forming a trust, under state law. The organizing document must explicitly limit the organization’s purposes to one or more exempt purposes and permanently dedicate its assets to those purposes.3eCFR. 26 CFR 1.501(c)(3)-1 It must also include a dissolution clause directing that any remaining assets go to another 501(c)(3) organization or a government entity if the foundation ever shuts down.4Internal Revenue Service. Dissolution Provision Under Section 501(c)(3)
After incorporating, the organization applies for federal tax-exempt status by filing Form 1023 with the IRS. The current user fee is $600, or $275 if the organization qualifies for the streamlined Form 1023-EZ.5Internal Revenue Service. Form 1023 and 1023-EZ: Amount of User Fee The application asks for detailed information about planned activities, governance, and financial projections.
What Keeps the Tax Exemption in Place
Earning 501(c)(3) status is only the start. The foundation must be both organized and operated exclusively for exempt purposes, which include religious, charitable, scientific, educational, and literary activities, among others.6Office of the Law Revision Counsel. 26 USC 501 The word “exclusively” has been read to mean “primarily” in practice, but even a single non-exempt purpose can be fatal if it’s more than an insubstantial part of the organization’s activities.
Two absolute prohibitions apply. No part of the foundation’s net earnings may benefit any private shareholder or individual, which rules out dividends, bonuses, or sweetheart deals for founders, board members, and their families.7Internal Revenue Service. Inurement/Private Benefit: Charitable Organizations And the foundation is completely barred from participating in political campaigns for or against any candidate for public office. Even indirect support, such as publishing materials that favor a candidate, can result in revocation of tax-exempt status and excise taxes under Section 4955.6Office of the Law Revision Counsel. 26 USC 501
Self-Dealing and Disqualified Persons
The self-dealing rules under Section 4941 are where most private foundations run into trouble. They prohibit nearly all financial transactions between the foundation and its “disqualified persons,” a category that extends well beyond the founder. It includes substantial contributors (anyone who has given more than $5,000 if that amount exceeds 2% of total contributions), foundation managers, owners of more than 20% of an entity that is a substantial contributor, family members of all of the above, and entities in which those people hold more than 35% ownership.8Internal Revenue Service. IRC Section 4946 – Definition of Disqualified Person
Prohibited transactions include selling or leasing property between the foundation and a disqualified person, lending money in either direction, and paying unreasonable compensation. Penalties are steep and layered. A disqualified person who engages in self-dealing owes an initial tax of 10% of the amount involved for each year the transaction remains uncorrected, and if the problem isn’t fixed within the taxable period, an additional 200% tax kicks in.9Office of the Law Revision Counsel. 26 USC 4941 – Taxes on Self-Dealing A foundation manager who knowingly participates faces an initial 5% tax and an additional 50% if they refuse to agree to correction.
The Other Excise Taxes on Private Foundations
Self-dealing is one of several excise tax traps in Chapter 42 that public charities don’t face.
Net Investment Income Tax
Every private foundation exempt under Section 501(a) pays a flat 1.39% excise tax on its net investment income each year. That covers interest, dividends, rents, royalties, and net capital gains, and the flat rate replaced the old two-tier system in 2020.10Office of the Law Revision Counsel. 26 USC 4940
Taxable Expenditures
Section 4945 imposes a 20% initial tax on amounts a private foundation spends on lobbying, attempting to influence elections, making grants to individuals without IRS-approved procedures, or making grants to organizations that aren’t public charities without exercising expenditure responsibility. If the expenditure isn’t corrected, the tax rises to 100%. Foundation managers who knowingly approve a taxable expenditure owe a personal 5% tax, with an additional 50% if they refuse to help correct it.11Office of the Law Revision Counsel. 26 U.S. Code 4945 There is a narrow exception on lobbying: foundations can respond to written requests for technical advice from legislative bodies, and they can share nonpartisan research.
Excess Business Holdings
A private foundation and its disqualified persons generally cannot own more than 20% of the voting stock in any business enterprise. An exception raises the ceiling to 35% if the foundation can show that it and its disqualified persons together do not hold effective control of the business.12Internal Revenue Service. IRC Section 4943 The same rules apply to partnerships and joint ventures, using profits interest in place of voting stock.
Jeopardizing Investments
Foundation managers who fail to exercise ordinary business care in making investments risk a 5% initial tax on the foundation and a 5% personal tax on the manager. Each investment is judged on the facts at the time it was made, not with hindsight. No investment type is automatically disqualifying, but the regulations flag margin trading, commodity futures, puts, calls, straddles, and short selling for heightened scrutiny. If the investment isn’t removed from jeopardy within the taxable period, an additional 25% tax applies.13eCFR. Subpart E – Taxes on Investments Which Jeopardize Charitable Purpose
The 5% Annual Payout Rule
A private non-operating foundation must distribute a minimum amount for charitable purposes each year. The baseline is 5% of the fair market value of the foundation’s non-charitable-use assets, minus certain taxes the foundation has already paid. This “5% rule” exists to keep foundations from stockpiling wealth indefinitely without providing any public benefit.14Office of the Law Revision Counsel. 26 USC 4942
Qualifying distributions include grants to public charities, direct charitable expenditures, and certain administrative costs tied to running charitable programs, such as staff salaries, rent, and program-related travel. Investment management fees, custodial fees, and costs of attending investment conferences do not count.
Falling short is expensive. The initial tax is 30% of the undistributed amount, and if the shortfall isn’t corrected by the end of the taxable period, a 100% tax applies to whatever remains undistributed.14Office of the Law Revision Counsel. 26 USC 4942 In practice, the IRS will eventually take the full amount that should have been distributed.
What Donors Can Deduct
Donors who give to a private foundation face lower annual deduction limits than those who give to a public charity. Cash contributions to a private non-operating foundation are generally deductible up to 30% of the donor’s adjusted gross income, compared with 60% for cash gifts to public charities.15Internal Revenue Service. Charitable Contribution Deductions For donations of appreciated property such as real estate or closely held stock, the deduction to a private foundation is usually limited to the property’s cost basis rather than its current fair market value, capping out at 20% of AGI.
Publicly traded stock is a valuable exception. When a donor gives qualified appreciated stock to a private foundation, they can deduct the full fair market value rather than reducing it to cost basis. The stock qualifies as long as market quotations are readily available on an established securities market on the day it is contributed, and the donor and family haven’t donated more than 10% of the corporation’s outstanding stock.16Internal Revenue Service. Publication 526, Charitable Contributions
Contributions above the annual AGI limits aren’t lost. Excess deductions carry forward for up to five years.16Internal Revenue Service. Publication 526, Charitable Contributions For 2026, donors should be aware that new legislation has introduced a 0.5% AGI floor for itemized charitable deductions, meaning only the portion of total contributions above that threshold is deductible. A separate non-itemizer charitable deduction of up to $1,000 ($2,000 for joint filers) is available for cash gifts to public charities but does not apply to contributions to private foundations.
Governance and Annual Reporting
A foundation’s board of directors or trustees bears fiduciary responsibility for managing assets, ensuring grant recipients align with the mission, and overseeing investment strategy. That duty generally breaks into three obligations: the duty of care (making informed decisions), the duty of loyalty (putting the foundation’s interests above personal ones), and the duty of obedience (keeping the organization faithful to its stated purpose and applicable laws). Board members who fall short can face personal liability, particularly if their negligence enables a self-dealing transaction or a jeopardizing investment.
Every private foundation must file Form 990-PF with the IRS annually. The return is due by the 15th day of the fifth month after the foundation’s tax year ends, so May 15 for calendar-year filers. It reports investment income, qualifying distributions, officer compensation, and every grant made during the year.17Internal Revenue Service. About Form 990-PF Unlike a personal tax return, Form 990-PF is a public document. Late filings trigger a penalty of $25 per day, rising to $130 per day for organizations with gross receipts exceeding roughly $1.3 million.18Internal Revenue Service. Instructions for Form 990-PF A copy must also go to the state attorney general in any state where the foundation is required to register, the state where it has its principal office, and the state where it was incorporated.
Beyond federal filings, most states require charitable organizations to register before soliciting contributions from their residents, and foundations that operate or solicit across state lines may need to register in multiple jurisdictions.19Internal Revenue Service. Charitable Solicitation – State Requirements
What Happens When a Foundation Shuts Down
When a charitable foundation winds down, its remaining assets cannot go back to the founder or the founder’s family. Federal law requires that upon dissolution, assets go to another 501(c)(3) organization or to a government entity for a public purpose.4Internal Revenue Service. Dissolution Provision Under Section 501(c)(3) That requirement must appear in the foundation’s organizing documents from the beginning; the IRS won’t approve the 501(c)(3) application without it. A corporation that adopts a plan to dissolve must also file Form 966, and the foundation’s final Form 990-PF should reflect the distribution of all remaining assets. Founders who want the money to continue in a specific direction often name successor organizations in the dissolution clause, so a future board cannot redirect the assets elsewhere.