To find out who donated to a nonprofit, start by identifying what kind of nonprofit it is: private foundations and Section 527 political organizations must publicly disclose the names of their contributors, while public charities — the largest category of 501(c)(3)s — do not. For public charities, donor names are stripped from tax filings before release, so the practical path is a mix of IRS records, third-party databases, and the organization’s own voluntary acknowledgments in annual reports, on websites, and on building plaques.
What Form 990 Shows for Public Charities
Every tax-exempt organization files an annual return that is open to public inspection under federal law.1Office of the Law Revision Counsel. 26 USC 6104 – Publicity of Information Required From Certain Exempt Organizations and Certain Trusts The main form is Form 990, which reports revenue, expenses, executive compensation, program activities, and governance. Attached to it is Schedule B, which lists contributors of $5,000 or more (or, for certain broadly supported charities, the greater of $5,000 or 2% of total contributions).2Internal Revenue Service. Instructions for Schedule B (Form 990)
Here is the catch. For public charities, the IRS is required to remove the names and addresses of contributors from Schedule B before releasing it to the public.3Internal Revenue Service. Public Disclosure and Availability of Exempt Organizations Returns and Applications – Contributors Identities Not Subject to Disclosure The publicly available copy shows the amount given and the type of property (cash, stock, real estate), but not who gave it. If you are researching a museum, university, hospital, church, or most nonprofits you would recognize by name, this is where the paper trail ends.
Private Foundations: Donor Names Are Public
Private foundations are the clearest exception. These are organizations typically funded by a single family, individual, or corporation, and they file Form 990-PF. Their Schedule B is fully open to public inspection, including the names and addresses of substantial contributors.2Internal Revenue Service. Instructions for Schedule B (Form 990) If the nonprofit you are researching is classified as a private foundation, you can read the donor list directly off the return.
The stricter disclosure standard exists because private foundations are controlled by a small group and lack the broad public support base of public charities, so the law treats their funding sources as information the public is entitled to see.
Political Organizations (527s)
Section 527 political organizations — groups organized primarily to influence elections — must disclose their donors. They file Form 8872 with the IRS, reporting the name, address, occupation, and employer of anyone who contributes more than $200 in a calendar year. Form 8872 and its attachments are open to public inspection on the IRS website.4Internal Revenue Service. Instructions for Form 8872 When a 527 also files Form 990, its Schedule B contributor names are public as well.3Internal Revenue Service. Public Disclosure and Availability of Exempt Organizations Returns and Applications – Contributors Identities Not Subject to Disclosure
The 501(c)(4) Exception You Should Know About
Not every politically active nonprofit is a 527. Many groups organized as 501(c)(4) social welfare organizations spend heavily on elections while keeping their donor lists private, and they are not required to disclose contributor names or addresses to the public.3Internal Revenue Service. Public Disclosure and Availability of Exempt Organizations Returns and Applications – Contributors Identities Not Subject to Disclosure This is why 501(c)(4)s are often called “dark money” groups. One narrow federal window exists: when any person or group makes independent expenditures exceeding $250 regarding a federal election, it must report those expenditures to the FEC, and if the spending was funded by earmarked contributions over $200, those donors must be disclosed on the FEC filing.5Federal Election Commission. Instructions for FEC Form 5 and Related Schedules Many organizations structure their finances to avoid triggering this requirement.
Where to Actually Search
IRS Tax Exempt Organization Search
The IRS maintains a free searchable database where you can look up any tax-exempt organization by name or Employer Identification Number.6Internal Revenue Service. Tax Exempt Organization Search You can verify tax-exempt status, view determination letters, and download the Form 990 filings themselves. Filters let you narrow by return type, revocation status, and determination letter.7Internal Revenue Service. Tax Exempt Organization Search For a private foundation, this is where you can pull the 990-PF and read the contributor list. For a public charity, this is where you confirm that Schedule B will be redacted.
ProPublica Nonprofit Explorer and Candid (GuideStar)
ProPublica’s Nonprofit Explorer covers roughly 1.9 million active nonprofits and 18 million tax filings, and it makes older 990s much easier to find than the IRS site does. It shows revenue, expenses, and executive pay alongside downloadable copies of the original returns. Candid, which now hosts GuideStar, provides similar 990 access along with organizational profiles, mission statements, and leadership details. Basic searches on both are free.
Requesting Records From the Nonprofit Itself
Federal law lets you request copies directly from the organization. A nonprofit must make its annual returns available for inspection during regular business hours at its principal office and at any regional office with three or more employees, and it must provide copies on request.1Office of the Law Revision Counsel. 26 USC 6104 – Publicity of Information Required From Certain Exempt Organizations and Certain Trusts In-person requests must be filled immediately; written requests must be filled within 30 days. The organization can charge a reasonable fee for copying and mailing but cannot refuse. Returns must be available for a three-year period from the filing due date (including extensions) or the actual filing date, whichever is later, and the organization must also produce its original application for tax-exempt status on request.8Internal Revenue Service. Public Disclosure and Availability of Exempt Organizations Returns and Applications – Documents Subject to Public Disclosure Remember: for a public charity, the copy you receive will still have donor names redacted.
State Charity Records
Most states require nonprofits that solicit donations within their borders to register with a state agency, usually the Attorney General’s office or Secretary of State. These filings include registration statements and annual financial reports, and some break out how much of every dollar raised went to programs versus administration or fundraiser commissions. State records are usually searchable online for free or a small fee, and paper copies can be obtained through a public records request.
State filings, however, generally will not give you donor names. In Americans for Prosperity Foundation v. Bonta, the Supreme Court struck down California’s requirement that charities submit unredacted copies of Schedule B to the state, holding that blanket collection of major donor identities burdened First Amendment associational rights and was not narrowly tailored, especially where the state had other tools like subpoenas for actual investigations.9Supreme Court of the United States. Americans for Prosperity Foundation v. Bonta The ruling builds on the Court’s 1958 decision in NAACP v. Alabama, which protected membership lists from compelled state disclosure. After Bonta, state-level filings are unlikely to contain individual donor names for most charities.
What Nonprofits Publish Voluntarily
For public charities, voluntary disclosures often reveal more than any government filing. Annual reports frequently include donor honor rolls that group contributors into giving tiers, with labels like “Gold Circle” for gifts over $10,000 or “President’s Club” for those above $25,000. These lists give a clear sense of who supports the organization and roughly at what level.
Naming rights are even more direct. Hospital wings, university buildings, endowed professorships, and community centers routinely carry the names of major benefactors on plaques, facades, or in official titles, and these naming agreements are public and often permanent. Nonprofit websites, capital campaign pages, fundraising event pages, and press releases also name major donors regularly. If you are researching a specific charity’s funding, these are usually the fastest sources.
Legal Limits on Using Donor Information
Once you have donor names, there are limits on what you can do with them. Under federal election law, individual contributor information taken from FEC reports cannot be sold or used to solicit contributions (including charitable donations) or for any other commercial purpose.10Federal Election Commission. Sale or Use of Contributor Information Use in newspapers, books, and similar communications is allowed, as long as the primary purpose is not solicitation or commercial activity. The Bonta decision also stands as a reminder that donors have recognized First Amendment interests in their anonymity, and that evidence in the case included death threats against identified donors.9Supreme Court of the United States. Americans for Prosperity Foundation v. Bonta