W-4 Withholding Calculator

Form W-4, the Employee's Withholding Certificate, is an IRS form you complete and give to your employer so they know how much federal income tax to withhold from your paycheck. The current W-4 (redesigned in 2020) uses dollar amounts instead of allowances, and walks you through your filing status, multiple jobs, dependents, and any other adjustments to arrive at the right withholding amount.

You should update your W-4 whenever a significant life event changes your tax situation. Common triggers include getting married or divorced, having or adopting a child, taking on a second job, experiencing a major change in income, or buying a home. The IRS also recommends reviewing your withholding at the start of each year and after any tax law changes to make sure you are on track.

If you do not submit a W-4 to your employer, the IRS requires them to withhold federal income tax at the default rate — as if you are single with no adjustments. This default treatment often leads to over-withholding for employees who would qualify for a lower rate under their actual filing status. You can submit or update a W-4 at any time during the year.

When you or your spouse hold more than one job, the combined income can push you into a higher tax bracket, but each employer only withholds based on the wages they pay. This mismatch often results in under-withholding. To fix it, use Step 2 of the W-4 to check the box for multiple jobs, or use the IRS withholding estimator to calculate the additional amount per paycheck to enter on Line 4(c). Coordinating withholding across all jobs helps you avoid an unexpected tax bill.