Every 501(c)(3) organization must make available for public inspection its application for tax-exemption, including its Form 1023 or Form 1023-EZ and any attachments, supporting documents, and follow-up correspondence with the Internal Revenue Service. The same public inspection requirement applies to the organization's annual return, namely its
Form 990, Form 990-EZ, Form 990-PF, Form 990-T, and Form 1065, including any attachments, supporting documents, and follow-up correspondence with the Internal Revenue Service, with the exception of the names and addresses of donors on Schedule B. Annual returns must be publicly available for a three-year period beginning with the due date of the return, including any extension of time for filing. A private nonprofit organization,
GuideStar, provides information on 501(c)(3) organizations.
ProPublica's Nonprofit Explorer provides copies of each organization's Form 990 and, for some organizations, audited financial statements. WikiCharities, is a nonprofit database of nonprofits and charities by name, location, and topic, that allows each organization to report its financials, leadership, contacts, and other activities. However, Open990 was a searchable database of information about organizations that had to shut down due to IRS delays in posting information online. ==Limitations on political activity==