Circular E

Employer's Tax Guide (Publication 15, Circular E)

About This Book

IRS Publication 15 (Circular E): Employer's Tax Guide

Publication 15 (Circular E) is the official IRS guide covering employers' federal payroll tax responsibilities, including withholding rules and reporting requirements. It is available as an HTML page or PDF download directly from the IRS.

What It Covers

  • Tax Withholding: How to calculate federal income tax, Social Security, and Medicare withholdings from employee paychecks.
  • Deposit Schedules: When and how to deposit withheld taxes via EFTPS (Electronic Federal Tax Payment System).
  • Filing Requirements: Guidance on periodic and annual forms, including Form 941, Form 940, and W-2/W-3.
  • Current Limits: Key figures such as the 2026 Social Security wage base of $184,500 and standard FICA rates.

Key Payroll Tax Rates

Tax Employer Employee
Social Security 6.2% 6.2% (up to wage base limit)
Medicare 1.45% 1.45% (+ 0.9% on wages over $200,000)
FUTA Varies N/A

Practice Tests Using This Book

This book is required or recommended for 3 licensing exams. Our practice tests include questions based on this material.