What each box on your W2 means

Your W2 form has 14 numbered boxes plus several unlabeled ones. Each box reports a different type of income or tax withholding from your employer. The IRS uses these boxes to match what your employer reported against what you report on your tax return. If the numbers don't match, the IRS will send you a letter asking for an explanation.

The form is split into two halves. The top half (boxes 1 through 6) shows your wages and the federal, Social Security, and Medicare taxes your employer withheld. The bottom half (boxes 12 through 20) shows additional income, tax-advantaged deductions, and state or local tax information. Boxes 7 through 11 sit in the middle and report Social Security and Medicare wages separately.

You will receive a copy of your W2 by January 31 of the year after you earned the income. Your employer sends copies to you, to the IRS, and to your state tax authority. When you file your tax return, you use the numbers from your W2 to fill in your income and verify that the right amount of tax was withheld.

Key Takeaways

  • Box 1 shows your taxable wages for federal income tax purposes, which is the number you use to calculate your federal tax on your return.
  • Boxes 2, 4, and 6 show federal income tax, Social Security tax, and Medicare tax that your employer already withheld from your paychecks.
  • Box 12 lists additional income or pre-tax deductions coded by letter, such as contributions to a 401(k) or health insurance premiums.
  • Boxes 17 through 20 show state and local income tax withheld and state wages, which you use if you file a state or local return.
  • If any number on your W2 looks wrong, contact your employer's payroll department to request a corrected form before you file your return.

Boxes 1 through 6: Federal wages and withholding

Box 1 (Wages, tips, other compensation) is the number you use on your federal tax return. It includes your salary or hourly wages plus any tips you reported to your employer. It does not include pre-tax deductions like 401(k) contributions or health insurance premiums — those are subtracted before this number is calculated. This is your taxable wages for federal purposes.

Box 2 (Federal income tax withheld) shows how much federal income tax your employer took out of your paychecks throughout the year. When you file your return, this number is your tax credit. If you withheld more than you owe, you get a refund. If you withheld less, you owe the difference. The amount withheld depends on the W4 form you filled out when you started the job.

Box 3 (Social Security wages) and Box 4 (Social Security tax withheld) are paired. Box 3 shows the wages subject to Social Security tax, which is capped at a certain amount each year (the cap changes annually). Box 4 shows the 6.2% Social Security tax your employer withheld. If you worked for multiple employers in the same year and your total wages exceeded the cap, you may have overpaid Social Security tax, which you can claim as a credit on your return.

Box 5 (Medicare wages and tips) and Box 6 (Medicare tax withheld) work the same way. Box 5 shows all wages subject to Medicare tax — there is no cap, so this is usually the same as Box 1. Box 6 shows the 1.45% Medicare tax your employer withheld. If your income is above a certain threshold (which varies by filing status), you may also owe an additional 0.9% Medicare tax, which you calculate on your return.

Boxes 7 through 11: Social Security and Medicare detail

These boxes break down Social Security and Medicare information by type. Box 7 (Social Security tips) shows tips you reported to your employer that are subject to Social Security tax. Box 8 (Allocated tips) shows tips your employer allocated to you if you work in food service or another tipped industry and the total tips reported by all employees fell short of 8% of gross sales.

Box 9 is not used on current W2 forms. Box 10 (Dependent care benefits) shows the value of dependent care benefits your employer provided, such as a subsidized daycare program. This amount is usually not taxable if it meets certain conditions. Box 11 (Nonqualified plans) shows distributions from a nonqualified deferred compensation plan, which is rare for most workers.

Box 12: Pre-tax deductions and additional income

Box 12 uses letter codes to report different types of pre-tax deductions and additional income. Each code appears on a separate line with a dollar amount. The most common codes are D (401(k) contributions), E (403(b) contributions for nonprofit employees), F (403(b) catch-up contributions), G (457(b) contributions for government employees), and H (457(b) catch-up contributions).

Other common codes include S (pre-tax health insurance premiums), T (pre-tax adoption benefits), V (pre-tax health savings account contributions), and W (pre-tax dependent care account contributions). These amounts reduce your taxable wages, so they do not appear in Box 1. If you see a code you don't recognize, the IRS website has a full list of Box 12 codes and what each one means.

Post-tax deductions — such as Roth 401(k) contributions or after-tax health insurance premiums — do not appear in Box 12. They are already included in Box 1 because they do not reduce your taxable income.

Boxes 13 through 20: Checkboxes, state tax, and other information

Box 13 contains three checkboxes. The first checkbox marks whether you are a statutory employee (a specific classification that affects how you report self-employment income). The second marks whether your employer provided sick pay under certain government programs. The third marks whether you are a third-party sick pay recipient. Most workers will see no checkboxes marked.

Boxes 15 through 20 report state and local income tax information. Box 15 shows the state where you worked and earned income. Box 16 shows your state wages (which may differ from Box 1 if your state has different rules). Box 17 shows state income tax withheld. Box 18 shows local income tax withheld. Boxes 19 and 20 show local wages and local tax withheld if your employer withholds for a city or county tax.

If you worked in multiple states or localities during the year, your W2 will show separate state and local sections for each one. You use these numbers when you file your state and local tax returns. Some states do not have income tax, so those boxes will be blank.

What to do if your W2 has an error

Compare your W2 to your final paystub from your employer. The numbers should match closely — Box 1 should equal your year-to-date gross pay, and Box 2 should equal your year-to-date federal withholding. If you spot a difference, contact your employer's payroll department right away and ask them to issue a corrected W2 (called a W2-c).

Your employer must send you a corrected W2 and file it with the IRS. This process can take several weeks, so report errors as soon as you notice them. Do not file your tax return until you have the corrected form — filing with wrong numbers can delay your refund or trigger an IRS notice.

If your employer refuses to correct the error or you cannot reach them, you can file your return using the correct numbers and attach a written explanation. Keep copies of your paystubs and any correspondence with your employer as proof of the discrepancy.

How to use your W2 when filing your return

When you file your federal return, you enter the amount from Box 1 on line 1a of Form 1040 (wages, salaries, tips). The IRS automatically receives a copy of your W2 from your employer, so they will check that your reported income matches. If you have multiple W2s from different employers, add up all the Box 1 amounts and enter the total.

Box 2 (federal withholding) goes on line 25 of Form 1040 as a tax credit. If you file using tax software, it usually pulls this number directly from your W2. The software also uses Box 12 codes to calculate your adjusted gross income correctly — for example, it subtracts 401(k) contributions from your taxable income.

If you file a state or local return, you use Boxes 16 through 20 the same way. Enter your state wages and state withholding on your state return. Some states have different rules about what counts as taxable income, so your state W2 wages may not match your federal wages.

Frequently Asked Questions

Why is Box 1 different from my gross pay on my paystub?

Box 1 excludes pre-tax deductions like 401(k) contributions, health insurance premiums, and dependent care account contributions. Your gross pay on your paystub includes these amounts before they are deducted. Box 1 is your taxable wages for federal income tax purposes, which is lower than your gross pay.

What does it mean if Box 12 has multiple codes?

Each code in Box 12 represents a different type of deduction or income. You may have a D code for 401(k) contributions and an S code for health insurance premiums on the same W2. Each code and amount appears on a separate line. Add them all up to see your total pre-tax deductions.

Do I need to report my W2 if I file electronically?

No. Tax software reads the information from your W2 and fills in the correct lines automatically. You still need to have your W2 in front of you to verify the numbers are correct, but you do not type them in manually if you use software or file online.

What if I lost my W2 and need to file my return?

Contact your employer and request a duplicate copy. If your employer is out of business or unreachable, you can request a wage and income transcript from the IRS using Form 4506-C or by logging into your IRS account online. The transcript shows what the IRS received from your employer.

Can I claim a refund if Box 2 shows more withholding than I owe?

Yes. When you file your return, the IRS compares your total tax owed to your total withholding (Box 2). If you withheld more than you owe, you receive a refund. If you withheld less, you owe the difference. The refund is calculated automatically when you file.