The Mechanics of Payroll Withholding
When you look at your pay stub, the federal income tax line is determined by statutory algorithms published by the IRS in Publication 15-T.
Federal Taxes 1 min read • Tax Year 2026
How Federal Income Tax Withholding Works on Your Paycheck
A step-by-step breakdown of how payroll processors use IRS Form W-4 and percentage method tables to determine federal tax withholdings.
By PayNumera Editorial Team, Payroll & Tax Research Group · Reviewed by Verified Editorial Review, CPA / Enrolled Agent Technical Standards
Published · Updated
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Official Sources
See the government publications referenced in this guide:
- Official Source ↗Publication 15-T: Federal Income Tax Withholding MethodsInternal Revenue Service (IRS)
- Official Source ↗Form W-4: Employee’s Withholding CertificateInternal Revenue Service (IRS)