Charitable, etc., contributions and gifts
The primary section governing the income tax deduction for charitable contributions. It is fundamental to fundraising for most 501(c)(3) organizations.

Percentage Limitations
Sets the limits on how much an individual or corporation can deduct for charitable contributions in a given tax year, generally as a percentage of their adjusted gross income (AGI) or taxable income.

50% Charities (Public Charities)
Lists the organizations (churches, schools, hospitals, and publicly supported charities) that qualify for the most favorable charitable contribution limits (50% or 60% of AGI). These are also the organizations defined as public charities under § 509(a)(1).

Public Charity Definition – Churches
Defines “a church or a convention or association of churches” as a type of organization qualifying for the highest charitable contribution deduction limits, thus classifying them as public charities.

Public Charity Definition – Educational Organizations
Defines educational organizations (schools, colleges, etc.) with regular faculty, curriculum, and an enrolled student body as public charities for donation deductibility purposes.

Public Charity Definition – Hospitals & Medical Research
Defines hospitals and certain medical research organizations as public charities, allowing donors to take the maximum charitable deduction for their contributions.

Governmental Units
Defines a state, a U.S. possession, or any political subdivision thereof, as well as the United States or the District of Columbia, as an entity qualifying for maximum charitable contribution deductions, effectively classifying them as public charities for donation purposes.

Certain Private Foundations
This section confers public charity status for contribution purposes to specific types of private foundations, such as private operating foundations, flow-through foundations, and pooled common funds.

Publicly Supported Organizations
This is a major category of public charity that receives substantial support from governmental units or the general public. This is a key cross-reference for organizations qualifying as publicly supported under IRC § 509(a)(1).

Agricultural Research Organizations
Grants public charity status to organizations directly engaged in continuous agricultural research in conjunction with a land-grant college or university, provided they are committed to spending contributions for such research within five years.

Contributions to Donor Advised Funds
Specifies the percentage limitations for charitable contributions made by an individual to a donor advised fund (DAF).

Exemption from tax on corporations, certain trusts, etc.
The foundational section that lists the types of organizations exempt from federal income tax, including the well-known 501(c)(3) category.

List of exempt organizations
The master list of all categories of tax-exempt organizations. It contains over two dozen paragraphs describing different types of entities, from social clubs (501(c)(7)) to business leagues (501(c)(6)) to charitable organizations (501(c)(3)).

Corporations Organized Under Act of Congress
Organizations that are created by an Act of Congress and are instrumentalities of the United States, such as Federal Credit Unions. They are exempt from tax without needing to file an application.

Charitable, Religious, Educational, Scientific, etc., Organizations
Corporations organized for the exclusive purpose of holding title to real property, collecting income from that property, and turning over the entire amount, less expenses, to another exempt organization.

Charitable, Religious, Educational, etc., Organizations
Defines the most common type of nonprofit, exempt for purposes that are charitable, religious, educational, scientific, literary, testing for public safety, fostering national or international amateur sports competition, or preventing cruelty to children or animals. Contributions to these organizations are generally tax-deductible.

Civic Leagues, Social Welfare Organizations, and Local Employee Associations
Nonprofit organizations operated exclusively for the promotion of social welfare. Their earnings must be devoted to charitable, educational, or recreational purposes.

Labor, Agricultural, and Horticultural Organizations
Organizations without net earnings inuring to any member, established to better the conditions of those engaged in labor, agriculture, or horticulture, improve their products, and develop higher efficiency.

Business Leagues, Chambers of Commerce, etc.
Associations of persons having a common business interest, whose purpose is to promote that interest and not to engage in a regular business of a kind ordinarily carried on for profit. Includes chambers of commerce and real estate boards.

Social and Recreational Clubs
Clubs organized for pleasure, recreation, and other nonprofitable purposes, substantially all of the activities of which are for such purposes and no part of the net earnings of which inures to the benefit of any private shareholder.

Fraternal Beneficiary Societies and Associations
Organizations operating under a lodge system for the exclusive benefit of their members, which provide for the payment of life, sick, accident, or other benefits to the members or their dependents.

Voluntary Employees’ Beneficiary Associations (VEBAs)
Associations providing for the payment of life, sick, accident, or other benefits to their members or their dependents, provided no part of the net earnings inures to the benefit of any private shareholder or individual.

Domestic Fraternal Societies and Associations
A lodge, order, or association that operates under the lodge system, devotes its net earnings exclusively to religious, charitable, scientific, literary, educational, and fraternal purposes, and does not provide for the payment of life, sick, or accident benefits.

Teachers’ Retirement Fund Associations
Local associations of a purely local character, whose income consists solely of amounts received from public taxation, assessments on the teaching salaries of members, and income from investments.

Benevolent Life Insurance Associations, Mutual Companies, etc.
Includes benevolent life insurance associations of a purely local character, mutual ditch or irrigation companies, and mutual or cooperative telephone companies, provided 85% or more of the income is collected from members for the sole purpose of meeting losses and expenses.

Cemetery Companies
Cemetery companies owned and operated exclusively for the benefit of their members or which are not operated for profit, and any corporation chartered solely for the purpose of the disposal of bodies by burial or cremation.

State-Chartered Credit Unions, Mutual Reserve Funds
Credit unions without capital stock organized and operated for mutual purposes and without profit, and corporations or associations without capital stock organized before September 1, 1957, for providing reserve funds for, and insurance of shares in, domestic building and loan associations.

Mutual Insurance Companies or Associations
Insurance companies or associations other than life or marine if the gross receipts for the taxable year do not exceed $600,000, and more than 50 percent of such gross receipts consist of premiums.

Cooperative Organizations to Finance Crop Operations
Corporations organized by a farmers’ cooperative marketing or purchasing association for the purpose of financing the ordinary crop operations of members of such association.

Supplemental Unemployment Benefit Trusts
A trust or trusts forming part of a plan providing for the payment of supplemental unemployment compensation benefits to an individual because of his involuntary separation from employment resulting directly from a reduction in force, the discontinuance of a plant or operation, or other similar conditions.

Employee Funded Pension Trust
A trust created before June 25, 1959, forming part of a plan for the payment of benefits under a pension plan funded only by contributions of employees.

Post or Organization of Past or Present Members of the Armed Forces
A post or organization of past or present members of the Armed Forces of the United States, or an auxiliary unit or society of, or a trust or foundation for, any such post or organization.

Group Legal Services Plan Organizations

Black Lung Benefit Trusts
A trust established in writing, created or organized in the United States, for the sole purpose of satisfying liabilities of a person for black lung benefits, paying insurance premiums for such liabilities, and paying administrative costs.

Withdrawal Liability Payment Fund
A trust created or organized in the United States to provide funds to meet the liability of employers withdrawing from a multiemployer pension plan.

Veterans Organizations (created before 1880)
Any association organized before 1880, more than 75 percent of the members of which are present or past members of the Armed Forces and a principal purpose of which is to provide insurance and other benefits to veterans or their dependents.

Section 4049 ERISA Trusts

Real Property Title-Holding Corporations with Multiple Parents
A corporation or trust organized for the exclusive purposes of acquiring, holding title to, and collecting income from real property, and remitting the entire amount of income from such property (less expenses) to its shareholders or beneficiaries.

State-Sponsored High-Risk Health Coverage Organizations
Any organization established by a State exclusively for the purpose of providing medical care on a not-for-profit basis to high-risk individuals who cannot obtain health insurance coverage.

State-Sponsored Workers’ Compensation Reinsurance Organization

Any organization established by a State, created before June 1, 1996, exclusively for the purpose of reimbursing its members for losses under workers’ compensation acts.

National Railroad Retirement Investment Trust
The National Railroad Retirement Investment Trust established under section 15(j) of the Railroad Retirement Act of 1974.

Qualified Nonprofit Health Insurance Issuers
A qualified nonprofit health insurance issuer which has received a loan or grant under the CO-OP program under section 1322 of the Affordable Care Act.

General Requirements for Charitable Hospitals
This is the general rule establishing that for a hospital organization to be recognized as a 501(c)(3) tax-exempt entity, it must meet the four additional requirements outlined in section 501(r).

Community Health Needs Assessments
This section specifically requires a hospital facility to adopt, and make widely available to the public, an implementation strategy to meet the community health needs identified in its Community Health Needs Assessment (CHNA).

Termination of Private Foundation Status
Outlines the rules and procedures for terminating a private foundation’s status, including the imposition of a termination tax unless the foundation transfers its assets to a public charity or operates as one for 60 months.

Termination by Asset Distribution
Allows a private foundation to terminate its status tax-free by distributing all of its net assets to one or more public charities described in § 170(b)(1)(A) (i.e., 509(a)(1) organizations) that have operated continuously for at least 60 months.

Special Rules for Termination
Provides special rules that allow a private foundation to terminate its status without incurring the termination tax, either by distributing all assets to a 509(a)(1) public charity or by operating as a public charity itself.

Operation as a Public Charity
Details the requirements for a private foundation to terminate its status by successfully operating as a public charity under section 509(a)(1), (2), or (3) for a continuous 60-month period.

Aggregate Tax Benefit
Defines the “aggregate tax benefit,” which is the total tax benefit received by the foundation and its substantial contributors. The termination tax is the lower of this amount or the foundation’s net assets.

Substantial Contributor
Defines a “substantial contributor” for the purposes of calculating the aggregate tax benefit upon termination of a private foundation’s status.

Special rules with respect to section 501(c)(3) organizations
Requires new organizations to apply for recognition (Form 1023) to be treated as § 501(c)(3) and presumes such organizations are private foundations unless they notify the IRS otherwise.

Governing Instruments
Requires private foundations to include specific provisions in their organizing documents (e.g., Articles of Incorporation) that mandate income distribution and prohibit acts defined in Chapter 42 (self-dealing, excess business holdings, etc.).

Private foundation defined
Defines what a private foundation is, generally by establishing it as the default status for 501(c)(3) organizations unless they can prove they are a public charity.

Private Foundation Definition
This is the foundational section that defines what a “private foundation” is. It operates by exclusion, meaning it states that any U.S. charitable organization described in Section 501(c)(3) is considered a private foundation unless it meets the specific criteria outlined in subsections 509(a)(1), 509(a)(2), 509(a)(3), or 509(a)(4). In essence, its main purpose is to differentiate private foundations from public charities.

Publicly Supported Organizations
This section describes the first, and most common, category of organizations that are excluded from the private foundation definition. These are often considered “classic” public charities. This category includes churches, schools, hospitals, and medical research organizations. It also includes organizations that receive a substantial portion of their financial support from governmental units or from direct or indirect contributions from the general public.

Public Support and Revenue Organizations
This section outlines another way for an organization to qualify as a public charity. It applies to organizations that receive more than one-third of their support from a combination of gifts, grants, contributions, membership fees, and gross receipts from activities related to their exempt purpose (e.g., ticket sales for a performance). A key feature is that these organizations must also receive no more than one-third of their support from gross investment income.

Supporting Organizations
This defines a “supporting organization,” a distinct type of public charity. Unlike the other categories, these organizations achieve their public charity status through their close relationship with one or more established public charities described in 509(a)(1) or 509(a)(2). They must be organized and operated exclusively for the benefit of, to perform the functions of, or to carry out the purposes of the supported public charity.

Imposition of Tax on Unrelated Business Income

Imposes a tax on the unrelated business taxable income (UBTI) of certain tax-exempt organizations, including charitable, religious, and educational organizations, at corporate or trust tax rates.

Unrelated business taxable income
Defines the income subject to the unrelated business income tax (UBIT), which is income from a trade or business that is regularly carried on and not substantially related to the organization’s exempt purpose.

Unrelated Business Taxable Income (UBTI)
Defines “unrelated business taxable income” as the gross income derived from any unrelated trade or business regularly carried on by an exempt organization, less the deductions directly connected with carrying on that trade or business.

Income from Publicly Traded Partnerships
Specifies that an exempt organization’s share of gross income from a publicly traded partnership is automatically treated as gross income from an unrelated trade or business.

Modifications to UBTI
Lists specific types of income that are excluded when calculating unrelated business taxable income, such as dividends, interest, royalties, and most capital gains.

Certain Amounts from Controlled Entities
Provides an exception to the general exclusion for interest, annuities, royalties, and rents, making them taxable as UBTI if received from a controlled entity.

Unrelated trade or business
Works with IRC § 512 to define what activities constitute an “unrelated trade or business,” the income from which is subject to tax. It specifies the activity must be a trade or business, regularly carried on, and not substantially related to the organization’s exempt functions.

Advertising, etc., activities
Establishes the “fragmentation rule,” clarifying that an activity carried on for the production of income does not lose its identity as a trade or business merely because it is carried on within a larger aggregate of similar activities (such as commercial advertising within an exempt periodical).

Unrelated Debt-Financed Income
States that income derived from property that is financed by debt and is not related to the organization’s exempt purpose is subject to the unrelated business income tax.

Political Organizations
Provides the rules for the taxation of political organizations, such as political parties, campaign committees, and political action committees (PACs).

Excise Tax Based on Investment Income
Imposes an excise tax on the net investment income of most domestic private foundations.

Tax on Net Investment Income
Establishes the excise tax rate (currently 1.39%) on a private foundation’s net investment income.

Tax on Unrelated Business Income for Certain Organizations
Addresses the coordination of the excise tax with the tax on unrelated business income for certain exempt operating foundations.

Exempt Operating Foundation
Defines an “exempt operating foundation,” which is a type of private foundation that is exempt from the excise tax on net investment income.

Taxes on self-dealing
Imposes an excise tax on acts of “self-dealing” between a private foundation and its disqualified persons.

Taxes on Failure to Distribute Income
Imposes an excise tax on private foundations that fail to make a minimum amount of “qualifying distributions” each year for charitable purposes.

Initial Tax
Sets the initial tax rate on a private foundation’s “undistributed income” for any taxable year, which has not been distributed before the first day of the second (or any succeeding) taxable year following such taxable year.

Undistributed Income
Defines “undistributed income” as the amount by which the distributable amount for a taxable year exceeds the qualifying distributions made out of such distributable amount for that year.

Qualifying Distributions Defined
Defines “qualifying distributions,” which are the payments and set-asides made by a private foundation to accomplish its exempt purposes, and which count toward meeting its minimum distribution requirement.

Certain Contributions to Controlled Organizations
Provides rules for when contributions to controlled organizations can be considered qualifying distributions.

Operating Foundations
Defines an “operating foundation,” which is a type of private foundation that is directly active in conducting charitable activities and is not subject to the minimum distribution requirement.

Operating Foundation Definition
Provides the specific tests an organization must meet to be classified as a private operating foundation, including the income test and one of three other tests (assets, endowment, or support test).

Assets Test
Details the “assets test,” where substantially more than half of the foundation’s assets are devoted directly to the active conduct of its exempt-purpose activities.

Endowment Test
Details the “endowment test,” where the foundation normally makes qualifying distributions directly for the active conduct of its exempt-purpose activities in an amount not less than two-thirds of its minimum investment return.

Support Test
Details the “support test,” where the foundation normally receives substantially all of its support from the general public and from five or more exempt organizations which are not disqualified persons.

Community Foundation
Defines a community foundation or trust for purposes of the 1-year pass-through of contributions.

Taxes on Excess Business Holdings
Imposes an excise tax on the “excess business holdings” of a private foundation in any business enterprise.

Excess Business Holdings
Defines “excess business holdings” and sets the permitted holdings of a private foundation in a business enterprise, generally 20% of the voting stock, reduced by the percentage of voting stock owned by all disqualified persons.

Exception for Donor Advised Funds
Provides an exception to the excess business holdings rules for certain holdings in a business enterprise that are held by a donor advised fund.

Taxes on investments which jeopardize charitable purpose
Imposes an excise tax on private foundations for making investments that jeopardize the carrying out of any of the foundation’s exempt purposes.

Taxes on Taxable Expenditures
Imposes an excise tax on private foundations for making any “taxable expenditures.”

Taxable Expenditure
Defines “taxable expenditure,” which includes amounts paid for lobbying, influencing elections, making grants to individuals for travel or study (unless certain requirements are met), or for any non-charitable purpose.

Expenditure Responsibility
Refers to grants made to an organization (other than a 501(c)(3) public charity) and requires the foundation to exert all reasonable efforts to establish that the grant is spent solely for the purpose for which it was made.

Activities Not Considered Lobbying
Lists activities that are not considered attempts to influence legislation, such as providing technical advice to a governmental body or making available the results of nonpartisan analysis.

Definitions and Special Rules
Provides definitions and special rules used in applying the private-foundation excise-tax provisions, including the term “disqualified person” and related attribution rules.

Disqualified Person Definition
Defines “disqualified person” for purposes of the private foundation excise taxes, covering substantial contributors, foundation managers, certain 20% owners, and family members of these individuals.

Trusts Treated as Private Foundations
Requires certain charitable trusts that are not tax-exempt to follow the same rules and restrictions that apply to private foundations.

Application of Taxes to Certain Nonexempt Trusts
Applies the private foundation excise taxes to certain nonexempt charitable and split-interest trusts.

Charitable Trusts
Specifies that nonexempt charitable trusts where all of the unexpired interests are devoted to charitable purposes are subject to the private foundation rules.

Taxes on Certain Foreign Organizations
Applies certain taxes and rules to foreign organizations that are private foundations.

Taxes on Political Expenditures of Section 501(c)(3) Organizations
Imposes an excise tax on 501(c)(3) organizations that make political expenditures, and a separate tax on the managers of the organization who agree to the expenditure.

Taxes on Excess Benefit Transactions
Imposes excise taxes on “excess benefit transactions” between a tax-exempt organization and a disqualified person, such as unreasonable compensation or improper use of the organization’s assets.

Excess Benefit Transaction
Defines an “excess benefit transaction” as any arrangement where a disqualified person receives more value from a tax-exempt organization than they provide in return, including unreasonable compensation or improper economic benefits.

Person Described
Defines the specific individuals treated as disqualified persons for supporting organizations, including substantial contributors, their family members, and 35-percent controlled entities.

Tax on Excess Tax-Exempt Organization Executive Compensation
Imposes an excise tax on an applicable tax-exempt organization equal to the rate of corporate tax on the sum of remuneration in excess of $1 million and any excess parachute payment paid to a covered employee.