Private and public foundations operate under different rules and behave differently as funders. Learn how the distinction shapes grant strategy, eligibility, and approach.

“Foundation” is the most overloaded word in grant seeking. It covers organizations that operate in fundamentally different ways: from a private family endowment with a single donor to a community-wide public charity holding hundreds of funds.

If you treat all foundations alike, you’ll write the wrong proposal to the wrong funder. The legal distinction between private and public foundations isn’t arcane, it changes how the funder makes decisions, how transparent its giving is, and how you should approach it.

This guide explains the difference and what it means for your grant strategy.

TL;DR: Quick Answers

What’s the difference? A private foundation is funded by one source (a family, an individual, a company) and is heavily regulated. A public charity, including community foundations, is funded broadly from the public and operates under different rules.
How does it affect your approach? Private foundations are often relationship-driven, narrower, and harder to access; public foundations and community foundations tend to be more accessible.
Why does it matter for research? Private foundations file Form 990-PF (rich data); public charities file Form 990. Both are public, but the data differs.
Which should you pursue? Both, deliberately, in a balanced 12-month grant strategy.

What Makes a Foundation “Private”

A private foundation is a 501(c)(3) organization funded primarily by a single source, an individual, a family, a corporation, an endowment. Most of its income comes from investments of that endowment rather than ongoing public donations.

Because private foundations are concentrated and unaccountable to the public in the way charities are, the IRS regulates them tightly. They must distribute roughly 5% of assets annually, file the detailed Form 990-PF, and follow specific rules about self-dealing and grants to non-charities.

The practical consequence: private foundations have a clear pile of money they have to give away each year, but they’re often staffed lightly, give within narrow priorities, and rely heavily on relationships and trust rather than open competition. Many of the largest, best-known funders (Ford, Hewlett, MacArthur, Robert Wood Johnson, Bezos, etc.) are private foundations.

That “pile of money” has grown fast. According to Candid, total foundation assets crossed $1.5 trillion just five years after passing $1 trillion in 2019, growth of roughly 60% in five years, with investment returns driving about 70% of that increase. To put the concentration in perspective, Gates, Ford, and Lilly Endowment together hold more than $60 billion, and total foundation investments equal roughly 3% of the entire U.S. stock market. That growth feeds real grantmaking: Giving USA (2025 report) reports foundation giving hit $109.81 billion in 2024, up 2.4%, the third straight year foundation grantmaking has topped $100 billion. See our 2026 grant statistics roundup for the full breakdown.

What Makes a Foundation “Public”

A public charity is a 501(c)(3) that meets a public-support test, demonstrating it draws funding from a broad base of donors rather than one source. Community foundations are the classic example, but many grantmaking organizations qualify as public charities.

Public charities file the standard Form 990, and many operate as public foundations (also called grantmaking public charities). Some operate donor-advised funds (DAFs), others run their own grantmaking programs, others do both.

The practical consequence: public foundations are often more open to applications, more transparent about their processes, and more responsive than private foundations. They’re often the right starting point for newer organizations.

How the Distinction Shapes Funder Research

When you research a funder (see how to research a funder), the foundation type tells you what data you’ll find.

Private foundations file 990-PFs, which list every grant they made, with grantee name, amount, and often purpose. This is the richest funder-intelligence document available in nonprofit philanthropy. Read it through your funder research, see reading IRS Form 990s.
Public charities (including most community foundations and many public foundations) file Form 990, which lists grants on Schedule I. Less detailed than 990-PF, but still useful.

Both filings are public. ProPublica’s Nonprofit Explorer, Candid’s GuideStar, and grant databases all surface them.

How the Distinction Shapes Your Approach

Approaching a private foundation:

Relationships matter more. A warm introduction, a board connection, or a program-officer conversation often opens doors that an unsolicited application can’t.
Many do not accept unsolicited proposals at all, you may need a letter of inquiry first, or an invitation.
Priorities are often narrow. Strict alignment with what they’ve previously funded, visible in the 990-PF, is critical.
Award sizes vary, but private foundations frequently make larger awards than community foundations and often fund general operating support once trust is established.

Approaching a public foundation or community foundation:

More accessible, often with clear application windows.
Often welcomes a pre-application conversation.
Geographic focus matters, community foundations fund within a defined region.
Award sizes are usually smaller per grant but the pool is broader; a community foundation may grant from many different funds with different priorities.

A Quick Note on Corporate Foundations

Many companies operate a separate corporate foundation, which is legally a private foundation funded by the company. It behaves like a private foundation (annual giving requirement, 990-PF filing) but with priorities tied to the company’s interests, see corporate giving programs. Some companies also do direct corporate giving outside any foundation.

Building a Balanced Foundation Strategy

Your 12-month grant strategy should include both private and public foundation prospects:

Public and community foundations for accessibility, relationship-building, and steady wins, especially valuable for newer organizations.
Private foundations for larger awards and longer-term partnerships, especially once you have a track record.
Corporate foundations and direct corporate giving for industry alignment and local community presence.

Pair them with federal and state funding for a complete mix.

How Grantboost Helps Across Foundation Types

Funder research across private and public foundations is fragmented, different filings, different data sources, different access models. Grantboost scans funding sources continuously and surfaces scored, mission-matched opportunities across private foundations, public foundations, community foundations, and corporate giving programs, so the entire foundation landscape sits in one pipeline.

Drafts come back in your organization’s voice (see training AI on your past proposals), structured for the type of foundation you’re approaching, whether that calls for a polished letter of inquiry to a private funder or a full proposal to a community foundation.

Try Grantboost free and build a foundation strategy that covers every type.

Private vs. Public Foundations: How the Distinction Shapes Your Grant Strategy