IRS Publication 15: Employer’s Tax Guide

IRS Publication 15 (also known as Circular E) explains employer responsibilities for withholding, depositing, reporting, paying, and correcting federal employment taxes. It is the primary federal reference employers use to manage payroll tax compliance.

Key takeaways

• Publication 15 covers federal employment taxes only (not state or local taxes). Employers must follow state rules for state withholding and reporting.
• It explains how to withhold federal income tax, Social Security, and Medicare from employees’ wages.
• The publication outlines deposit schedules, filing requirements, corrections, and employer reporting obligations (for example, Forms 941 and 944).
• Withholding tables previously in Publication 15 are now in Publication 15‑T; the IRS also provides an online withholding assistant.

What Publication 15 covers

Publication 15 organizes practical guidance employers need for payroll tax compliance, including:
* Employer Identification Numbers (EINs) and legal definitions of employees
* Hiring and paying family members and household employees
* Employee Social Security numbers and wage reporting requirements
* What counts as wages and other compensation, including tips and supplemental wages
* How to withhold federal income tax, Social Security, and Medicare
* Deposit rules and payment schedules for withheld taxes
* Filing and adjusting employment tax returns (Forms 941, 944)
* Reporting adjustments and correcting errors
* Federal Unemployment Tax (FUTA)
* Required employee notices, such as information about the Earned Income Credit (EIC)
* Payroll period considerations and recordkeeping

Withholding rules and tools

• Employees complete Form W-4 to determine federal income tax withholding; they can update it when their circumstances change.
• If an employee does not provide a W-4, Publication 15 specifies default withholding procedures.
• The IRS moved detailed withholding calculation tables and methods into Publication 15‑T (Federal Income Tax Withholding Methods). Employers can also use the IRS Income Tax Withholding Assistant for Employers to calculate withholding.

How employers should use Publication 15

• Consult Publication 15 to establish and maintain payroll processes that meet federal requirements.
• Use it alongside Publication 15‑A (Employer’s Supplemental Tax Guide) for additional employer-specific guidance.
• Check the IRS website for the latest edition, legislative updates, and electronic tools.
• Combine federal guidance with state tax agency resources to ensure full compliance with state withholding and reporting obligations.

Practical notes

• Publication 15 is a reference for routine payroll decisions (how much to withhold, when to deposit taxes, which forms to file).
• Keep payroll records and follow the correction procedures in the guide if withholding or reporting mistakes occur.
• When in doubt about specific situations—such as fringe benefits, unusual wage types, or multi-state employment—consult the IRS publications and, if needed, a tax professional.

For current versions and interactive tools, access Publication 15 and related materials on the IRS website.