In federal income tax, a “person” is not just a human being. Section 7701(a)(1) of the Internal Revenue Code defines the word to include an individual, a trust, an estate, a partnership, an association, a company, or a corporation.1Office of the Law Revision Counsel. 26 U.S.C. 7701 – Definitions Anything that fits that list can be a taxpayer, meaning it can be required to file, required to pay, and penalized when it doesn’t. A related provision defines a “taxpayer” as any person subject to any internal revenue tax, which closes the loop.2GovInfo. 26 U.S.C. 7701 – Definitions
Congress wrote the list broadly on purpose. The practical effect is that a family trust, a two-person partnership, and a multinational corporation all sit inside the same category, with enforceable duties attached to each.
Individuals
Living human beings are the most familiar type of person for tax purposes. The category covers U.S. citizens (whether born in the United States, its territories, or naturalized), resident aliens who meet the green card or substantial presence tests, and nonresident aliens who earn income from U.S. sources.3Internal Revenue Service. Foreign Persons U.S. citizens and residents owe tax on their worldwide income regardless of where they live.
Your identity in the system is tied to a Taxpayer Identification Number. For most people that is a Social Security Number. If you are ineligible for an SSN but have a federal filing obligation, the IRS issues an Individual Taxpayer Identification Number instead.4Internal Revenue Service. Taxpayer Identification Numbers (TIN)
A dependent claimed on someone else’s return is still a person in their own right. A child with investment income or a part-time job may need to file. The IRS recognizes two types of dependents, a qualifying child and a qualifying relative, and each has its own income, support, and residency tests.5Internal Revenue Service. Rev. Proc. 2025-326Internal Revenue Service. Dependents
Corporations
A corporation is treated as its own person, entirely separate from the shareholders who own it. It files its own return, pays its own taxes, and bears its own liability. Its income is taxed at the corporate level, and shareholders pay tax again when they receive dividends. That two-layer structure is what people mean by “double taxation.” Assets, debts, and records belong to the corporation rather than to any individual owner, and the IRS enforces the separation strictly.
S Corporations
An S corporation is still a corporation and still a person under the tax code, but it gets pass-through treatment by election. Instead of paying corporate-level income tax, it passes income, losses, deductions, and credits through to shareholders, who report those items on their personal returns.7Internal Revenue Service. S Corporations The S corporation itself still owes certain entity-level taxes on built-in gains and passive income.
When an S corporation owns 100% of a subsidiary, it can elect to treat that subsidiary as a Qualified Subchapter S Subsidiary. After the election, the subsidiary is no longer a separate corporation for tax purposes, and its income and assets roll into the parent’s return.8Internal Revenue Service. About Form 8869, Qualified Subchapter S Subsidiary Election The subsidiary effectively stops being a separate person for income tax.
Partnerships
A partnership qualifies as a person under the tax code even though it doesn’t pay income tax itself. It files an annual information return (Form 1065) reporting all of its income, deductions, and credits, and each partner reports their share on their own return.9Internal Revenue Service. Partnerships The IRS uses the partnership return to cross-check the partners.
The filing obligation is where personhood bites. For returns required to be filed in 2026, a partnership that files late or fails to file faces a penalty of $255 per partner for each month the return is overdue, up to a maximum of 12 months.10Internal Revenue Service. Rev. Proc. 2024-40 For a ten-partner firm, that reaches $30,600 in penalties before any tax is due. The base amount is adjusted for inflation each year.11Office of the Law Revision Counsel. 26 U.S.C. 6698 – Failure to File Partnership Return
LLCs and Disregarded Entities
Limited liability companies are the most common source of confusion here, because the tax code doesn’t list “LLC” as a type of person at all. An LLC’s tax treatment depends on how many owners it has and whether it makes an election.
A single-member LLC is treated by default as a “disregarded entity.” The IRS ignores it for income tax purposes, and the LLC’s activity flows directly to the owner’s personal return as if the LLC didn’t exist.12Internal Revenue Service. Single Member Limited Liability Companies The LLC still provides liability protection as a legal matter, but for income tax it is not a separate person.
A multi-member LLC defaults to partnership treatment and becomes a person the way any partnership is. Either type of LLC can elect to be treated as a corporation instead by filing Form 8832.13Internal Revenue Service. About Form 8832, Entity Classification Election The state creates the LLC, but the IRS decides whether to treat it as a person, and a one-page form can change that answer.
Estates and Trusts
When someone dies, a new taxable person comes into existence. The decedent’s estate takes over whatever income-producing assets the individual held and files its own return on Form 1041.14Internal Revenue Service. Estates and Trusts The estate is temporary, lasting only until debts are settled and property is distributed, but while it exists it has its own tax bracket and its own obligations.
A trust works the same way. Whether revocable, irrevocable, or charitable, the IRS treats it as its own person capable of holding property, earning income, and owing tax. The executor or trustee has to obtain an Employer Identification Number and file returns on the entity’s behalf.15Internal Revenue Service. Information for Executors A fiduciary who mishandles these duties can be held personally liable for the taxes the estate or trust owes.
Associations, Companies, and Other Groups
The statute’s list also names “association” and “company,” which function as catch-all categories. They pull in organizations that don’t fit neatly into the corporation or partnership box: a joint-stock company that issues shares without formal incorporation, an investment club, a professional group pooling resources for a common purpose.16Internal Revenue Service. LLC Filing as a Corporation or Partnership
The IRS looks at how a group actually operates rather than what it calls itself. An informal club that collects dues, invests money, and generates income has the hallmarks of a person that needs to file. Skipping formal paperwork does not push a group outside the tax system.
Tax-Exempt and Government Entities
Being exempt from income tax does not mean an organization isn’t a person. A 501(c)(3) nonprofit is very much a person under the code. It must apply for exempt status, file annual returns, and follow strict rules on how it operates. If it pays unreasonable compensation to insiders or drifts from its exempt purposes, excise taxes apply.17Internal Revenue Service. Exemption Requirements – 501(c)(3) Organizations “Exempt” describes the tax liability, not the personhood.
Federal, state, and local government entities sit in a similar place. They are generally exempt from income tax on revenue derived from public functions but still have obligations as persons for other tax purposes, particularly employment taxes. A government employer must withhold federal income tax and, in many cases, Social Security and Medicare taxes from employee wages.18Internal Revenue Service. Government Entities and Their Federal Tax Obligations
U.S. Persons and Foreign Persons
The tax code draws a hard line between U.S. persons and foreign persons. A “United States person” includes U.S. citizens, resident aliens, domestic partnerships, domestic corporations, and most domestic estates and trusts.19Internal Revenue Service. Classification of Taxpayers for U.S. Tax Purposes Everyone else is a foreign person.
Foreign persons who earn income from U.S. sources face a default withholding rate of 30% on payments such as dividends, interest, rent, and wages. The payer must withhold and send that amount to the IRS before the foreign person receives the money.20Office of the Law Revision Counsel. 26 U.S.C. 1441 – Withholding of Tax on Nonresident Aliens Tax treaties can reduce or eliminate that rate, but claiming the lower rate requires the right paperwork.
U.S. persons face obligations running the other way. Any U.S. person with a financial interest in foreign bank accounts exceeding $10,000 in aggregate at any point during the year must file a Report of Foreign Bank and Financial Accounts (FBAR) with FinCEN.21FinCEN.gov. Report Foreign Bank and Financial Accounts The rule reaches every category of person: individuals, corporations, partnerships, trusts, and estates.
What Happens If You Ignore the Obligation
Every entity that qualifies as a person is subject to penalties for noncompliance, and the IRS runs a graduated enforcement system.
The most common late-filing penalty is 5% of the unpaid tax for each month or partial month the return is overdue, up to a maximum of 25%.22Internal Revenue Service. Failure to File Penalty The clock starts the day after the deadline, and partial months count as full months.
Willful failure to file is a criminal misdemeanor punishable by up to one year in prison and a fine of up to $25,000 ($100,000 for corporations).23Office of the Law Revision Counsel. 26 U.S.C. 7203 – Failure to File Return or Pay Tax Tax evasion is a separate and more serious charge, a felony carrying up to five years in prison and a fine of up to $100,000 ($500,000 for corporations).24Office of the Law Revision Counsel. 26 U.S.C. 7201 – Attempt to Evade or Defeat Tax The line between the two is intent. Not filing is bad; actively hiding income or deceiving the IRS is worse.
These penalties apply across the whole list. A trust that doesn’t file owes penalties. A partnership that misses its deadline owes penalties per partner. A corporation that evades taxes can be prosecuted. The broad definition of “person” is the mechanism that lets the IRS enforce the tax laws against every entity generating income in the United States.