Form W-4
Also called: W-4, Withholding certificate
The IRS form you give your employer to set how much federal income tax is withheld from each paycheck, based on filing status, jobs, and dependents.
Since 2020, the W-4 no longer uses allowances. It has five steps: personal information and filing status, multiple jobs or a working spouse, dependent credits, other adjustments (other income, deductions, and extra withholding), and your signature.
Withholding is an estimate of your yearly tax spread across paychecks. If too little is withheld you'll owe at tax time; too much and you get a refund — money you could have had all year. Update your W-4 after marriage, a new job, a baby, or a big change in income.
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Disclaimer: Definitions are general education, not financial, tax, or legal advice. Figures are for the 2026 tax year unless noted.