What Is Form W-4?
Form W-4 is the US form employees give their employer to indicate how much federal income tax to withhold from their pay. It captures filing status, multiple jobs or a working spouse, dependents, other income, deductions, and any extra withholding. Employers use it with IRS tables to calculate each paycheck's withholding.
When It Is Updated
A new W-4 can be submitted at any time, for example after marriage, a new child, or a second job, to adjust withholding.
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🔗 Related Terms
More Taxes Terms
- Additional Medicare Tax
- Adjusted Gross Income (AGI)
- Alternative Minimum Tax (AMT)
- Capital Gains Tax
- Capital Loss
- Child Tax Credit
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Last updated: September 27, 2026. This definition is for general educational purposes only. It is not financial, investment, tax, legal, or medical advice, and it does not recommend any product or course of action. For decisions about your own situation, consult a qualified professional.