A §501(c)(3) organization is exempt from federal income tax on income derived from activities that further its exempt purposes, can receive tax-deductible charitable contributions, and is eligible for grants from private foundations. The status comes with significant compliance obligations: an annual Form 990 that is public record, restrictions on political activity, unrelated business income tax (UBIT) on income from activities not substantially related to the exempt purpose, and for private foundations, a separate regime of excise taxes and restrictions. Understanding the framework before formation prevents costly mistakes that are difficult to unwind.
Public charity: Receives a substantial portion of its support from the general public or government (the "public support test"). Subject to standard §501(c)(3) rules. Donors deduct contributions up to 60% of AGI for cash gifts. Much lighter regulatory burden than private foundations.
Private foundation: Does not meet the public support test - typically funded by a single individual, family, or corporation. Subject to the §4940-4945 excise tax regime: 1.39% investment income tax, self-dealing prohibitions, mandatory 5% distribution requirement, restrictions on jeopardizing investments, taxable expenditure rules. Much heavier compliance burden.
The default: A new §501(c)(3) organization is presumed to be a private foundation unless it demonstrates it qualifies as a public charity.
To qualify under §501(c)(3), an organization must satisfy both the organizational test and the operational test.
Organizational test (IRC §501(c)(3)): The articles of incorporation or governing document must: (1) limit the organization's purposes to one or more exempt purposes (religious, charitable, scientific, educational, literary, testing for public safety, fostering amateur sports competition, preventing cruelty to children or animals); (2) prohibit the organization from using its assets or earnings for the private benefit of any individual; and (3) require that upon dissolution, assets be distributed to another §501(c)(3) or to the government.
Operational test: The organization must be operated primarily for exempt purposes. It may not allow private inurement - no part of net earnings may inure to the benefit of any private shareholder or individual. It may not have substantial non-exempt activities. It may not participate or intervene in any political campaign on behalf of or in opposition to any candidate for public office (the absolute prohibition).
Income from activities not substantially related to the organization's exempt purpose is subject to the Unrelated Business Income Tax (UBIT) under IRC §511-513. UBIT is taxed at the regular corporate rate (21%) or trust rates depending on the organization's form. The three-part test for UBIT: (1) it is income from a trade or business, (2) the trade or business is regularly carried on, and (3) the business is not substantially related to the organization's exempt purpose.
Common UBIT situations: rental income from debt-financed property (the debt-financed property rules under §514 make otherwise-excluded rent partially taxable); advertising revenue from publications; income from fitness centers, travel tours, or retail operations open to the general public; and income from parking lots or garages. Common UBIT exclusions: dividends, interest, rents from property not subject to debt financing, royalties, and gains from the sale of property not held as inventory.
Private foundations are subject to a separate regime of excise taxes that do not apply to public charities. Key taxes: §4940 - 1.39% tax on net investment income (dividends, interest, rents, royalties, and capital gains from non-mission investments); §4941 - self-dealing tax (5% on disqualified persons who engage in prohibited transactions with the foundation - includes sales, loans, furnishing of goods); §4942 - failure to distribute income (30% excise tax on undistributed income; foundations must distribute at least 5% of asset value annually); §4943 - excess business holdings; §4944 - jeopardizing investments; §4945 - taxable expenditures (grants to organizations not §501(c)(3), expenditures for political campaigns, grants to individuals without proper procedures).
Most §501(c)(3) organizations must file an annual information return: Form 990 (organizations with gross receipts over $200,000 or assets over $500,000), Form 990-EZ (smaller organizations), or Form 990-N (e-postcard for very small organizations with gross receipts normally under $50,000). Private foundations file Form 990-PF regardless of size. Form 990 is publicly available - the IRS publishes it and it is accessible through Guidestar/Candid. Compensation of the five highest-paid employees and all officers/directors is disclosed. Organizations routinely underestimate the reputational impact of the Form 990's public disclosure requirements.