A W-4 is the IRS Employee's Withholding Certificate. You fill it out and give it to your employer to tell them how much federal income tax to withhold from each paycheck. It does not get sent to the IRS — your employer keeps it on file.

Not unless your situation changes. Your current W-4 stays in effect until you submit a new one. The exception: if you claimed exempt status, you must renew it by February 15th of each year.

The old form used allowances (0, 1, 2...). The new form uses dollar amounts — other income, deductions, and dependent credits. The result is more accurate withholding, but the instructions are more confusing. That's why this site exists.

The modern W-4 doesn't use those numbers, but the concept applies. Leaving Step 3 blank mimics claiming 0 (maximum withholding). Adding dependents in Step 3 mimics claiming 1 or more. Our calculator gives you the exact amounts to enter.

Your employer withholds as if you are Single with no adjustments — the highest rate. You won't be penalized, but your paychecks will be smaller than necessary.

Only if you had zero tax liability last year AND expect zero this year. Claiming exempt otherwise means you'll owe all the tax at filing time, plus potential penalties.

Both of you need to complete Step 2, or at least one of you should. Without it, each employer withholds only based on their salary, and you'll likely underpay when the incomes are combined on your joint return.

Complete Step 2 on at least one of your W-4s. Simplest: check the box in Option C to withhold at the higher Single rate.

Enter your estimated annual freelance net income in Step 4(a). This causes extra withholding on each day-job paycheck to cover the freelance tax. Or make quarterly estimated payments directly to the IRS.

Your employer must implement it within 30 days — usually the next payroll cycle. Check your following paycheck to confirm.

Step 2 adjusts withholding when you have multiple W-2 income sources — two jobs, or you and your spouse both work. Without it, each employer withholds at too low a rate.

Yes. Your employer keeps it on file and does not submit it to the IRS. The IRS can request it during an audit, but it is not publicly accessible.

W-4 Frequently Asked Questions