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Private Foundations

6 分で読めます 更新日 Aug 08, 2026
A private foundation is a legal entity a family creates to pursue charitable goals, funded almost entirely by the family itself and governed by a board the family controls. Unlike a donor-advised fund, a private foundation is a standalone organization with its own tax status, filing obligations, and strict rules about how money can be used. Family offices commonly handle the administrative and grantmaking infrastructure that keeps a foundation running.
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What Is a Private Foundation?

A private foundation is a tax-exempt, nonprofit legal entity created and funded by a single donor, family, or corporation rather than the general public. The word "private" distinguishes it from a public charity, which raises money broadly from many unrelated sources. Families typically form a private foundation when they want a permanent, named institution to carry out their charitable mission across generations.

A private foundation sits outside the family office itself but is often deeply intertwined with it. The family office commonly provides the operational infrastructure — accounting, compliance tracking, grant administration — while the foundation's board sets direction and approves grants. Think of the foundation as the vehicle and the family office as the engine room that keeps it moving.

Board and Governance Duties

Every private foundation is governed by a board of directors or a board of trustees. Board members owe a fiduciary duty to the foundation's charitable mission — meaning they must act in the foundation's best interest, not their own. Families typically seat a mix of family members and independent advisors to bring outside perspective and reduce the risk of conflicts.

The board is responsible for approving the foundation's mission statement, investment policy, grantmaking guidelines, and annual budget. It also bears ultimate responsibility for legal compliance. In practice, a founder who sold her manufacturing company and seeded a foundation might chair the board while her adult children serve as directors — with a family governance framework, similar to what's described in family governance planning, guiding how decisions are made and how the next generation earns a seat at the table.

Good governance also means documented policies: conflict-of-interest policies, grant evaluation criteria, and meeting minutes. Regulators and auditors look for these records, and they protect board members personally. Families without formal documentation often find that the foundation becomes a source of family tension rather than shared purpose.

The Operating Burden: Filings, Distributions, and Rules

Running a private foundation carries a real administrative load. Foundations must file an annual information return with tax authorities — a public document that discloses grants made, officer compensation, investments, and more. Readers must work with qualified attorneys and CPAs to understand the specific forms, deadlines, and jurisdiction-specific requirements that apply to their situation.

The Minimum Distribution Concept

Private foundations in most jurisdictions are required to distribute a minimum amount each year for charitable purposes — commonly expressed as a percentage of the foundation's investment assets. This rule exists to prevent families from accumulating wealth in a tax-favored structure indefinitely without actually funding charity. The specific percentage and what counts toward satisfying it varies by jurisdiction and can change; always confirm current requirements with qualified legal counsel.

Self-Dealing Rules

Self-dealing rules are among the most consequential constraints a private foundation faces. Self-dealing refers to transactions between the foundation and "disqualified persons" — a legal category that typically includes the founding family, board members, major contributors, and entities they control. Even transactions that seem reasonable, like renting office space from a family member at fair market value, can trigger penalties under self-dealing rules.

The penalties for self-dealing can fall on the individual who participated in the transaction, not just the foundation. Families commonly find that understanding these rules early — before the foundation is established — saves significant cost and complexity later. This is an area where qualified legal counsel is not optional.

Excise Taxes and Investment Rules

Private foundations pay a modest excise tax on net investment income in many jurisdictions. They also face restrictions on owning large stakes in businesses — sometimes called "excess business holdings" rules — to prevent the foundation from functioning as a tax shelter for family-controlled companies rather than a genuine charitable vehicle.

Staffing and the Family Office's Role

Small foundations often have no dedicated staff at all. The family office absorbs the operational work: preparing the annual filing, tracking grants, managing the foundation's investment accounts, and coordinating with outside legal counsel. A controller or accountant on the family office team often handles the foundation's books as part of a broader role.

Larger foundations — those making dozens of grants a year or pursuing a specific programmatic strategy — commonly hire a dedicated philanthropy director or program officer. This person manages relationships with grantees, conducts due diligence on grant applications, and reports to the board. The family office then focuses on operations and compliance while the philanthropy director handles mission execution.

As a foundation grows, the boundary between family office and foundation can blur. Families commonly establish a management company structure that provides shared services — accounting, HR, technology — to both the family office and the foundation under a formal services agreement, which itself must be structured carefully to avoid self-dealing concerns.

The Grantmaking Process

Grantmaking is the foundation's core activity — the mechanism by which assets reach charitable causes. A well-run grantmaking process typically moves through several stages.

  1. Inquiry or letter of intent. Prospective grantees submit a brief description of their organization and proposed use of funds. The foundation screens these against its mission and published criteria.
  2. Full application. Qualified applicants submit a detailed proposal including budget, organizational financials, and program outcomes.
  3. Due diligence. Staff or board members verify the organization's legal status, review financials, and sometimes conduct site visits. Foundations must confirm grantees are recognized charitable organizations or conduct "expenditure responsibility" procedures for other types of recipients — a concept qualified counsel can explain in detail.
  4. Board approval. The board votes to approve, table, or decline grants. Minutes document the decision.
  5. Grant agreement and payment. Approved grants are documented in a written agreement specifying the purpose and any reporting requirements.
  6. Monitoring and reporting. Foundations commonly require grantees to report on how funds were used, which feeds back into renewal decisions.

Families often discover that building a consistent, documented grantmaking process is what separates a foundation that creates lasting impact from one that disperses money without measurable results.

Private Foundation vs. Donor-Advised Fund

A donor-advised fund (DAF) is the most common alternative families consider. A DAF is an account held within a public charity — a sponsoring organization — where the family contributes assets, receives an immediate tax deduction, and then recommends grants over time. The sponsoring organization, not the family, holds legal control of the assets.

The table below illustrates the conceptual differences. All specifics should be confirmed with qualified attorneys and CPAs; this is an illustrative comparison only.

Factor Private Foundation Donor-Advised Fund
Legal control of assets Family retains control through board Sponsoring organization holds legal title
Administrative burden High — annual filings, compliance, self-dealing rules Low — sponsoring organization handles compliance
Investment control Board directs investment policy Limited options set by sponsoring organization
Grantmaking flexibility Can fund internationally, individuals (with restrictions), scholarships, and program-related investments Generally limited to recognized public charities
Family naming and identity Full — foundation carries the family's name and brand Possible but less prominent
Minimum distributions Required by law (jurisdiction-specific) No legal minimum in most jurisdictions
Startup complexity Significant — legal formation, IRS recognition, governance documents Minimal — open an account with a sponsoring organization
Multi-generational design Highly customizable; can embed governance and succession rules Succession possible but less flexible

Families with a long-term philanthropic identity, a desire for full control, or complex grantmaking goals — such as funding international organizations or making program-related investments — commonly prefer the private foundation structure. Families seeking simplicity, lower cost, and a faster start often find a DAF meets their needs just as well, and some families use both in parallel.

Honest Tradeoffs to Consider

A private foundation is an organization, not just an account. It has legal obligations, costs, board meetings, annual filings, and compliance requirements that persist every year regardless of how active the grantmaking is. Families that underestimate this burden sometimes find the foundation becomes dormant or creates friction rather than fulfilling its intended purpose.

On the other side, the private foundation offers something a DAF cannot: a named institution the family fully controls, with the ability to embed governance structures, involve the next generation in meaningful roles, and build a grantmaking identity that outlasts the founder. For families where philanthropy is central to their identity and legacy, that trade is often worth making — with eyes fully open to the operating commitment it requires.

よくある質問

What is the difference between a private foundation and a public charity?
A private foundation is funded primarily by one family or source and controlled by a board the family appoints, while a public charity raises money from the general public and meets broader support tests. Private foundations face stricter rules — including minimum distribution requirements and self-dealing prohibitions — precisely because they are controlled by a small group. The distinction matters for tax deductions, compliance obligations, and what the organization can do with its money.
Can a family pay staff through their private foundation?
Foundations can pay reasonable compensation to staff who are not family members performing actual services. Compensating family members who are also disqualified persons — typically the founders and close relatives — is heavily regulated by self-dealing rules and can trigger significant penalties if not structured correctly. Families must work with qualified legal counsel before setting any compensation arrangements involving insiders.
Is there a minimum asset size to start a private foundation?
There is no universal legal minimum, but the practical economics suggest a foundation needs enough assets to cover ongoing compliance costs, annual filing requirements, and meaningful grantmaking while still meeting minimum distribution obligations. An illustrative example: a foundation funded with a few hundred thousand dollars may spend a disproportionate share on administration relative to grantmaking. Many families find a donor-advised fund more practical below a certain asset level, and qualified advisors can help evaluate the threshold that makes sense for a specific situation.
How does a family office typically support a private foundation?
Family offices commonly handle the foundation's bookkeeping, investment account oversight, grant payment processing, and coordination with outside legal and tax advisors. The family office may also prepare board meeting materials and track compliance deadlines, effectively serving as the foundation's back office. As the foundation grows, families often hire a dedicated philanthropy director to manage grantmaking while the family office continues to own the operational and financial infrastructure.
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