Private Foundation Directory

A directory of the largest US private foundations, ranked by total assets reported on IRS Form 990-PF. Coverage centers on independent, family, and operating foundations that file public 990-PF returns. Figures are drawn from each foundation’s most recent filing. Updated periodically.

This directory ranks US private foundations by total assets on their most recent IRS Form 990-PF filing. Total assets, not grants or revenue, is the headline metric, since a foundation’s endowment defines its scale. Figures reflect 2024 tax year filings, the most recent available from the IRS. The Type column is an editorial classification by Deep Institutional and should be reviewed. Foreign-domiciled foundations that file a US return, such as Wellcome and Volkswagen, are out of scope. Inception reflects the year each foundation was legally established or its predecessor charitable vehicle created, per the foundation’s own history page where available and IRS tax-exemption records otherwise; a number of entries, especially newer or lesser-documented family foundations, are dated to their IRS tax-exemption ruling year in the absence of a published founding narrative, and a few older foundations were later reorganized or renamed under a different structure, notably the Robert Wood Johnson Foundation (established 1936, reorganized into its present national form in 1972), the J. Paul Getty Trust (founded as the Getty Museum Trust in 1953, renamed and reorganized in 1983), the John D. and Catherine T. MacArthur Foundation (legally created in 1970, funded and active from 1978), and the W.K. Kellogg Foundation Trust No. 5315, whose own establishment year could not be confirmed with certainty from public sources and is shown here as approximate. The Gates Foundation is shown as a single entry: the organization operates through two legal vehicles, a grantmaking foundation and a separate trust that holds the endowment and funds it, which report substantially the same pool of assets on separate IRS filings, so listing both here would double count one endowment; the figure shown reflects the trust’s reported total assets, and the entity dropped “Bill & Melinda” from its name in January 2025. By contrast, the two Open Society entries, Foundation To Promote Open Society and Open Society Institute (which operates publicly as Open Society Foundations), are each other’s counterparts within George Soros’s philanthropic network but file separate 990-PFs against genuinely distinct, non-overlapping asset pools, so both are retained here. Figures are approximate and should be independently verified. Last reviewed 2026. Maintained by Deep Institutional.