How do I fill out the W-4 if I have two jobs?

If you have two jobs (or are married and both you and your spouse work), complete Step 2 of the W-4. The most accurate option is to use the IRS's Tax Withholding Estimator online. You can also use the Multiple Jobs Worksheet in the W-4 instructions. Without Step 2, each employer withholds as if that job is your only income, leading to significant under-withholding.

How often can I change my W-4?

You can submit a new W-4 to your employer at any time throughout the year. There is no limit on how many times you can change it. Changes take effect on your next paycheck after your employer processes the form.

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

If you don't submit a W-4, your employer must withhold at the highest rate — Single with no adjustments. This often leads to over-withholding. Always submit a W-4 when starting a new job.

Should I claim 0 or 1 on my W-4?

The current W-4 (2020 and later) doesn't use allowances of 0 or 1. Those numbers referred to the old form. On the current form, you enter dollar amounts or check boxes. If your situation is straightforward (one job, no dependents, standard deduction), you can complete only Step 1 and Step 5 and your withholding will be reasonably accurate.

W-4 Withholding Guide: Stop Over- or Under-Paying the IRS

What the W-4 Actually Controls

The W-4 (Employee's Withholding Certificate) tells your employer how much federal income tax to withhold from each paycheck. It does not affect FICA taxes (Social Security and Medicare) — those are always 7.65% of wages and are non-negotiable. The W-4 also doesn't affect state income tax withholding, which is handled by a separate state form.

Completing the W-4 correctly means your withholding will closely match your actual tax liability, avoiding both a surprise April bill and an unnecessarily large refund.

The 2020 Redesign: No More Allowances

If you haven't updated your W-4 since before 2020, your employer is using the old allowance system. The current W-4 is more direct: you enter dollar amounts in specific fields rather than claiming "allowances." This change makes the form more accurate but also more confusing for many employees. The IRS recommends completing a new W-4 whenever your financial situation changes.

The Five Steps of the W-4

Step 1: Personal information and filing status (single, married, or head of household). Step 2: Multiple jobs adjustment — use this if you or your spouse have more than one job. Step 3: Claim dependents — enter the Child Tax Credit amount (up to $2,000 per qualifying child). Step 4: Other adjustments — deductions, additional income (interest, dividends, freelance), or extra withholding per period. Step 5: Sign and date. Steps 2 through 4 are optional for simple situations.

When to Update Your W-4

File a new W-4 when you: get married or divorced, have a child or adopt, start or stop a second job, begin freelancing on top of your day job, buy a home (mortgage interest deduction), significantly change your income, or move to a different state. The IRS recommends reviewing withholding any time your tax situation changes materially. You can submit a new W-4 to your employer at any time — there's no limit on changes.

The goal: Owe $0 and get $0 back. A large refund means you over-withheld — you gave the government an interest-free loan all year. A large tax bill means you under-withheld and may owe a penalty if you underpaid by more than $1,000 (or 90% of your current-year tax).

Multiple Jobs and Household Income

This is the most common source of W-4 errors. Each employer withholds as if that job is your only income — the tax tables are designed for a single job. If you have two jobs or your spouse works, this leads to under-withholding because your combined income pushes you into higher brackets than each job individually would suggest. Use Step 2 of the W-4, or use the IRS Tax Withholding Estimator to calculate the correct extra withholding amount per paycheck.

Claiming Exempt — When It's Valid

You can write "EXEMPT" on your W-4 (in the Step 4c area) only if you had zero federal tax liability last year AND expect zero federal tax liability this year. This is valid for very low earners. For 2026, a single filer with income under about $15,000 (the standard deduction) would owe no federal income tax. Claiming exempt when you don't qualify is illegal and will result in a large bill plus interest and possible penalties.

This guide is for informational purposes only and does not constitute tax, legal, or financial advice. Tax laws change frequently. Consult a qualified tax professional for advice specific to your situation.