Internal Revenue Code for Business Owners Guide

The Internal Revenue Code for business owners is Title 26 of the U.S. Code, the federal tax law that the Internal Revenue Service (IRS) administers. It decides how each kind of business is taxed, which returns it files and what mistakes cost. This page is for people who own or run a U.S. business from Canada or India, or who live here on a visa.

Slide show: The Internal Revenue Code in seven slides

What it is
Title 26 of the U.S. Code, the federal tax law for every U.S. business.
Who it affects
Any business with U.S. income, including U.S. companies owned from Canada or India.
The rule
Your entity type sets your return. Foreign owners add Form 5472 or Form 1040-NR.
The number
C corporation rate: 21 percent. Section 179 limit for 2026: $2,560,000.
The deadline
S election: 2 months and 15 days after the year starts. Partnership and S corporation returns: 15th day of the third month.
The penalty
$25,000 for a missed Form 5472. Accuracy penalty: 20 percent. Civil fraud: 75 percent.
The tip
Ask your Canadian CPA or Indian CA how your home country treats the same entity.

Who does the Internal Revenue Code for business owners cover?

Business form	Default federal treatment	Choice
Sole proprietor; one-owner domestic LLC	Owner's return (Schedule C); self-employment tax can apply to an individual owner	LLC: Form 8832
Multi-member domestic LLC	Partnership, Form 1065	Form 8832
State-law corporation	Corporation; cannot check the box out	Form 2553 if eligible
C corporation	21 percent of taxable income; dividends taxed again	None
S corporation	Income passes to shareholders; up to 100 shareholders; one class of stock	Form 2553
Foreign entity	Own default rules; a Canadian "Corporation and Company" or Indian "Public Limited Company" is generally a corporation	Form 8832 if eligible

What does the Internal Revenue Code mean for a foreign-owned or cross-border business?

Situation	What the law says	What to check
One-owner U.S. LLC with a Canadian or Indian owner	Disregarded for income tax, yet treated as a corporation for Form 5472, filed with a pro forma Form 1120	Owner contributions, loans, distributions; foreign-owned LLC guide
U.S. subsidiary of a foreign parent	A foreign shareholder holding 25 percent or more makes it a reporting corporation; one Form 5472 per related party	Ownership chart; subsidiary guide
Nonresident alien owner	Resident rates on U.S. business income (Form 1040-NR); generally 30 percent or a treaty rate on U.S.-source dividends, interest and royalties	Where the work happens; nonresident guide
U.S. company paying a foreign person	Payer withholds, usually 30 percent unless a treaty or exemption applies	Form W-8 first; withholding guide
Foreign owner wanting S status	Not allowed for a nonresident alien shareholder	LLC or C corporation; entity types

Where to go next

The rules and checklist page holds the 2026 numbers and the Banyan-and-Birch Entity Walk. Related laws: FICA for payroll tax and the Bank Secrecy Act and FBAR for foreign accounts.

Official sources

This page summarizes public guidance in plain language. If anything here differs from the official source, the official source controls.

Please read: general information only

This page gives general information and education about a law that may affect businesses. It is not legal, tax, accounting or other professional advice and it is not a substitute for advice from a licensed attorney or CPA who knows your facts. Reading it does not create an attorney-client, CPA-client or any other professional relationship with CPA Tax Payroll and Accounting Corp. CPA Tax Payroll and Accounting Corp is a CPA firm, not a law firm: it does not give legal advice or represent anyone in legal matters.

Laws, thresholds, rates and penalties change often, and courts and agencies change how they apply them. We checked the figures against the official source on the date shown (last reviewed October 27, 2026), but we do not promise that this page is complete, current or free of errors, and we do not update it the moment a law changes. Whether a law applies to you depends on facts we do not have. Examples are invented and for illustration only.

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Internal Revenue Code: Guide for Foreign-Owned Businesses

What it is

Who it affects

The rule

The number

The deadline

The penalty

The tip

Who does the Internal Revenue Code for business owners cover?

What does the Internal Revenue Code mean for a foreign-owned or cross-border business?

Where to go next

Official sources

Related guides

Internal Revenue Code Checklist: 2026 Numbers, Penalties

US Business Entity Types and Tax Forms: Which Return Each One Files

Forms 5472 and 1120 for a US Subsidiary of a Foreign Parent

US Withholding on Payments to Foreign Persons: Chapter 3, Chapter 4, 1042 and 1042-S

Foreign-Owned LLC: US Tax and Reporting for Owners in India and Canada

US Tax for Nonresidents: FDAP and ECI Income Explained