How to Read Your W-2 Form: Every Box Explained

By the USPaycheckGuide Editorial Team · Reviewed by Shaharyar Abid · Last updated September 27, 2026

Your W-2 is the summary of your year of work. Knowing what each box means helps you file accurately and spot mistakes before they cost you.

1. What a W-2 Is

Employers send Form W-2 to employees and the IRS by the end of January. It reports your wages and the taxes withheld during the year. You use it to file your return, so it should match your final pay stub. Compare it with our guide on reading a pay stub.

2. Boxes 1 and 2: Wages and Federal Tax

Box 1 shows taxable wages, which excludes pre-tax contributions such as traditional 401(k) deferrals and many health premiums. Box 2 shows federal income tax withheld. These two numbers drive your federal return.

3. Boxes 3 to 6: Social Security and Medicare

Boxes 3 and 4 show Social Security wages and tax withheld (6.2% up to the annual wage base). Boxes 5 and 6 show Medicare wages and tax (1.45%, plus additional Medicare tax for high earners). Box 3 and 5 amounts can be higher than Box 1 because pre-tax retirement deferrals still count for FICA. Learn more in What Is FICA Tax?

4. Box 12 Codes

Box 12 lists special items with letter codes. Code D is traditional 401(k) deferrals, code AA is Roth 401(k), code W is employer HSA contributions and code DD is the cost of employer-sponsored health coverage, which is informational and not taxable.

5. Boxes 15 to 20: State and Local

These show your state, employer state ID, state wages and state income tax withheld, plus local tax where applicable.

6. What to Do If Something Looks Wrong

Compare Box 1 to your last pay stub year-to-date figures. If a name, Social Security number or amount is wrong, ask your employer for a corrected W-2c. Do not file until the numbers are correct.

7. A Sample Walkthrough

Imagine your W-2 shows $62,400 in Box 1, $6,200 in Box 2 and $66,000 in Box 3. The $3,600 difference between Box 1 and Box 3 is your traditional 401(k) deferral, which reduces taxable income but not Social Security wages. Box 4 would then show about $4,092 (6.2% of $66,000) and Box 6 about $957 (1.45% of Medicare wages). If those numbers look different, ask payroll to explain before you file.

8. Common Mistakes When Filing

• Using pay stub year-to-date totals instead of the final W-2.
• Typing Box 1 into the wrong return line.
• Ignoring a second W-2 from a job held only part of the year.
• Filing before receiving a corrected W-2c.

9. Key Takeaways

• Box 1 drives your federal return.
• Boxes 3 to 6 show FICA wages and tax.
• Box 12 codes reveal retirement and HSA contributions.
• Verify every box against your last pay stub.

10. Box-by-Box Walkthrough of the Form W-2

The W-2 has lettered boxes for identifying information and numbered boxes for money. Here is what each important box means and what to check.

• Boxes a to f: your Social Security number, your employer's EIN and address, and your name and address. A wrong Social Security number can delay your return, so verify it carefully.
• Box 1, wages, tips and other compensation: taxable wages for federal income tax after pre-tax deductions such as traditional 401(k) contributions and many health premiums.
• Box 2, federal income tax withheld: the total federal income tax taken from your paychecks.
• Box 3, Social Security wages: wages subject to Social Security tax, up to the annual wage base. This can be higher than Box 1 because 401(k) deferrals still count.
• Box 4, Social Security tax withheld: generally 6.2% of Box 3.
• Box 5, Medicare wages and tips: wages subject to Medicare tax with no wage base cap.
• Box 6, Medicare tax withheld: generally 1.45% of Box 5, plus 0.9% Additional Medicare Tax on wages above $200,000.
• Box 7, Social Security tips and Box 8, allocated tips: tip income reported to your employer or allocated to you.
• Box 10, dependent care benefits: amounts paid or reimbursed through a dependent care account. See dependent care FSA explained.
• Box 11, nonqualified plans: distributions from certain deferred compensation plans.
• Box 12, coded items: letters identify items such as D (traditional 401(k)), E (403(b)), AA (Roth 401(k)), W (employer HSA contributions), DD (cost of employer health coverage) and others.
• Box 13, checkboxes: statutory employee, retirement plan and third-party sick pay.
• Box 14, other: employer-specific items such as union dues or state disability insurance.
• Boxes 15 to 20: state and local wages and taxes.

11. A Pre-Filing Checklist for Your W-2

1. Confirm your name and Social Security number match your Social Security card.
2. Compare Box 1 with your final pay stub year-to-date gross minus pre-tax deductions.
3. Verify that Box 2 matches the total federal tax withheld on your last stub.
4. Check Box 4 against 6.2% of Box 3 and Box 6 against 1.45% of Box 5.
5. Add up the codes in Box 12 and compare with your contribution records.
6. Confirm your state and local information.
7. If you had more than one job, gather every W-2 before filing.

If any number looks wrong, contact your employer's payroll department and request a corrected form, called a W-2c. Filing with wrong information can create notices, delays and possible penalties.

12. Common W-2 Problems and How to Solve Them

• Missing W-2: employers must furnish forms by January 31. Contact them first; if it does not arrive, the IRS can help, and you may file using Form 4852 as a substitute with your best records.
• Wrong address: a mailing error can delay your form. Many employers provide electronic copies through payroll portals.
• Two W-2s from the same employer: this can happen after a business change. Report both.
• Box 1 lower than salary: normal when you contribute to pre-tax benefits.
• Unusual Box 12 codes: ask payroll what the code represents and confirm the amount.
• Different withholding than expected: compare with your W-4 elections. See how to fill out a W-4 and adjusting your W-4.

13. How Your W-2 Connects to Your Tax Return

On Form 1040, wages from your W-2 Box 1 go on the wages line, and Box 2 goes on the federal income tax withheld line. Your total tax is computed on taxable income, which starts with adjusted gross income (see what is adjusted gross income) and subtracts either the standard deduction or itemized deductions. If withholding exceeds your tax, you receive a refund; if not, you owe. See how tax refunds work and, if this is your first return, how to file taxes for the first time. For a preview of your paycheck each period, use the paycheck calculator and see how to read a pay stub.

14. W-2 vs 1099: Know Which You Are

Employees receive W-2s. Independent contractors receive 1099s and are responsible for self-employment tax and estimated payments. Misclassification is a common issue: if you work under an employer's control and schedule but receive a 1099, you may want to discuss classification with a tax professional or the IRS. Learn more in W-9 vs 1099, how quarterly estimated taxes work and the self-employment tax calculator.

15. Glossary of W-2 and Payroll Terms

• EIN: employer identification number, the employer's tax ID.
• Wage base: the annual limit on wages subject to Social Security tax.
• Pre-tax deduction: an amount deducted before income tax is calculated, such as traditional 401(k) contributions. See pre-tax deductions.
• Supplemental wages: bonuses and commissions, often withheld at a flat rate. See how commissions are taxed.
• Withholding: the amount your employer sends to the IRS on your behalf.
• W-2c: a corrected W-2.

16. How Long to Keep Your W-2

Keep W-2s with your tax returns for at least three years, and longer if you claim losses or credits that could be reviewed later. Store a digital copy in a secure location. Records help if you need to amend a return or verify past income for a loan application. For a bigger picture, read what is payroll tax and what is FICA tax.

17. Where to Get Your W-2 and What to Do If You Move

Most employers provide W-2s through an online payroll portal in late January, and many also mail paper copies. If you moved during the year, update your address with each employer and the IRS, and make sure your last employer has your current mailing address. If you worked for a company that closed, contact the state workforce agency or the IRS for help getting wage information. Your IRS online account also lets you view a wage and income transcript that shows W-2 data reported to the IRS, which can help you file accurately when a form is missing or late. For related information, read how to file taxes for the first time.

18. Common box 12 codes

Frequently Asked Questions

When will I get my W-2?

Employers must furnish it by January 31 for the prior tax year.

What if I never got my W-2?

Contact your employer first. If it does not arrive, the IRS can help you request it, and you may still file using pay stubs with Form 4852.

Why is Box 1 lower than my salary?

Pre-tax deductions such as traditional 401(k) contributions and health premiums reduce taxable wages.

Why do Box 1 and Box 3 differ?

Pre-tax retirement deferrals reduce Box 1 but not FICA wages in Boxes 3 and 5.

Can I file with a W-2 that has errors?

It is better to get a corrected W-2c first; otherwise you risk delays or notices.

What do I do if my employer files the wrong W-2 amount?

Ask them to issue a W-2c with the correct amounts and use the corrected form when you file. If it arrives after you file, you may need to amend your return.

Can I file taxes without my W-2?

You can file using a substitute form if you cannot obtain it, but it is best to get the official form first.

Where can I find old W-2s?

Ask your former employer, check payroll portals or request a wage and income transcript from the IRS online account.

Why does Box 3 exceed Box 1?

Traditional 401(k) contributions reduce Box 1 but not Social Security wages in Box 3.

Is a W-2 the same as a pay stub?

No. A pay stub shows earnings and deductions for a single pay period, while a W-2 summarizes the whole year. The year-to-date totals on your last pay stub should match your W-2, aside from small differences due to timing or reporting rules.

What does Box 12 code DD mean?

Code DD reports the total cost of employer-sponsored health coverage, including both the employer and employee portions. It is informational and is not taxable income. It helps you understand the value of your benefits.

Do I need to attach my W-2 to my tax return?

If you e-file, you generally enter the information and do not attach the form. If you file on paper, you attach Copy B, which shows federal tax withheld.

Why is box 12 code DD on my W-2?

It reports the total cost of employer health coverage for information only; it is not taxable and you do not enter it as income.

What is box 14 on my W-2?

An optional box employers use for items like state disability insurance, union dues or after-tax contributions; it is usually informational.

Why do I have two W-2s from one employer?

A mid-year payroll change or a merger can produce two; report both on your return.

What if box 2 is empty?

No federal income tax was withheld; you may owe tax when you file unless your income is low.

What is box 10 on a W-2?

Dependent care benefits your employer provided, such as dependent care FSA contributions; amounts over the yearly limit are added to taxable wages.

This article is for general education only and is not tax, legal or investment advice. Figures and rules change; confirm details with the IRS or a qualified professional before making decisions.