How often can I change my W-4?

Any time. Submit a new one to your employer whenever your situation changes (marriage, child, second job, side income, big change in deductions).

Does my W-4 affect my state tax?

No. Most states have their own W-4 equivalent (NY IT-2104, CA DE-4, etc.). Your federal W-4 only affects federal withholding.

What happens if I don't submit a W-4?

Your employer applies default withholding (single, no adjustments), which usually over-withholds. You can file a tax return to claim the refund.

Can I claim 'exempt'?

Only if you owed no federal income tax last year AND expect to owe none this year. Submit a fresh W-4 by February 15 each year to maintain exempt status. Most people do not qualify.

W-4 Guide (How to Fill Out a W-4)

The W-4 tells your employer how much federal tax to withhold from each paycheck. The 2020 version replaced the old allowance system. Most workers fill it out once and forget it. Smart workers revisit it annually.

In short

A W-4 is the IRS form that tells your employer how much federal income tax to withhold from each paycheck. You complete it in five steps: filing status, multiple jobs, dependents, other adjustments, and signature. It does not change the tax you owe — only how much is prepaid each period. Submit a new W-4 to your employer any time your situation changes.

PayslipIQ provides educational information and estimated calculations only. It does not provide tax, legal, financial, accounting, employment, benefits, or payroll advice. PayslipIQ is not a CPA firm, law firm, financial advisor, payroll provider, or tax authority. Always verify your paycheck, deductions, withholdings, and tax position with your employer's payroll department, a qualified CPA, the IRS, your state tax authority, or another appropriately qualified professional. Calculations are estimates; your actual paycheck may differ based on factors specific to your employer, location, benefits elections, and personal tax situation.

What the W-4 does

It tells your employer how much federal tax to take out of every paycheck on your behalf. It does not change your tax liability. Withholding is a prepayment, settled at filing time.

Step 1: Personal information

Name, address, Social Security Number, filing status. Filing status drives the bracket your employer applies. Single, Married Filing Jointly, Head of Household.

Step 2: Multiple jobs or spouse works

Three sub-options:

Use the IRS Tax Withholding Estimator (most accurate).
Use the Multiple Jobs Worksheet on page 3.
Check the box if you have two jobs paying similarly. Apply only to the higher-paying job.

If you skip Step 2 and your household has multiple incomes, you will likely under-withhold.

Step 3: Claim dependents

Multiply qualifying children under 17 by $2,000.
Multiply other dependents by $500.
Add the result and enter the total. This reduces your withholding.

Step 4(a): Other income

Interest, dividends, retirement distributions, side gig income. Adding it here increases withholding so you do not owe at year-end.

Step 4(b): Deductions

If you itemize, use the Deductions Worksheet on page 3. Adding deductions reduces withholding.

Step 4(c): Extra withholding

A flat dollar amount to add per pay period. Useful for fine-tuning, especially when other adjustments are insufficient.

Step 5: Sign and date

The W-4 is not valid without signature.

Common scenarios

Two-income household

Use the IRS Estimator or check the Step 2(c) box. Submit only on the higher-earning job.

Side gig + W-2

Add your side income to Step 4(a). Or pay quarterly estimated taxes via Form 1040-ES.

I want a smaller refund

Decrease Step 4(c). Or claim additional dependents in Step 3 if appropriate.

I want a larger refund

Increase Step 4(c). Adds a flat dollar amount to each paycheck.

Claiming exempt

You can claim exempt only if you owed no federal income tax last year and expect to owe none this year. Most people do not qualify.

Frequently asked questions

How often can I change my W-4?: Any time. Submit a new one to your employer whenever your situation changes (marriage, child, second job, side income, big change in deductions).
Does my W-4 affect my state tax?: No. Most states have their own W-4 equivalent (NY IT-2104, CA DE-4, etc.). Your federal W-4 only affects federal withholding.
What happens if I don't submit a W-4?: Your employer applies default withholding (single, no adjustments), which usually over-withholds. You can file a tax return to claim the refund.
Can I claim 'exempt'?: Only if you owed no federal income tax last year AND expect to owe none this year. Submit a fresh W-4 by February 15 each year to maintain exempt status. Most people do not qualify.