How large are the assets of the largest U.S. foundations?

I recently came across this fascinating dataset from the IRS, which has filings for all tax-exempt organizations in the United States. US foundations hold over $1.3 trillion in assets across 134,888 foundations, according to IRS data (2023).

The largest foundations are:

• Bill & Melinda Gates Foundation ($109bn),
• Wellcome Trust ($46bn)
• Lilly Endowment ($41bn),
• Ford Foundation ($20bn)
• William & Flora Hwelett Foundation ($15bn)

Together, these four foundations hold over 230 billion $US in assets – more than 17% of all assets of American foundations. One percent of all foundations hold over 70% of assets.

Could smaller foundations achieve greater efficiencies through increased collaboration or is this diversity of a “thousand flowers” ultimately more impactful in a diverse society?

Chart: US Foundations by Asset Size & State (Source: IRS)