What a W2 Form Is and Why Your Employer Sends It

A W2 form is a document your employer sends you each January showing how much you earned in the previous year and how much tax was withheld from your paychecks. You do not fill out a W2 — your employer does. The form arrives in the mail or electronically, and you use the numbers on it to complete your tax return.

If you are looking for instructions on how to fill in a W2 because you are an employer or payroll administrator, that is a different process. This guide covers what to do when you receive a completed W2 as an employee.

Key Takeaways

  • You receive a completed W2 from your employer; you do not fill it out yourself as an employee.
  • The W2 shows your gross income, federal and state taxes withheld, Social Security and Medicare taxes, and other deductions.
  • You use the numbers from your W2 to fill out your tax return on Form 1040 or through tax software.
  • If your W2 contains errors, contact your employer's payroll department to request a corrected form (Form W2-c).
  • Keep your W2 with your tax records for at least three years in case the IRS requests documentation.

Understanding Each Box on Your W2

A W2 contains numbered boxes, each reporting a different type of income or tax information. Box 1 shows your wages, tips, and other compensation subject to federal income tax. Box 2 shows federal income tax withheld from your paychecks. Boxes 3 and 5 show Social Security wages and Social Security tax withheld. Boxes 4 and 6 show Medicare wages and Medicare tax withheld.

Boxes 12 and 14 may contain additional information depending on your job — for example, contributions to a 401(k) plan, health insurance premiums, or other pre-tax deductions. Your employer fills in all these boxes based on your actual earnings and withholdings throughout the year. You will need these numbers when you file your tax return.

How to Use Your W2 When Filing Taxes

When you file your federal tax return, you enter the amount from Box 1 of your W2 on Form 1040, line 1a (wages, salaries, tips). If you use tax software like TurboTax or TaxAct, the software will prompt you to enter this information, and it will automatically carry the number to the correct line. If you file by paper, write the Box 1 amount directly on the form.

The federal tax withheld (Box 2) goes on a different line of Form 1040 and reduces the amount of tax you owe or increases your refund. State tax information from your W2 goes on your state tax return, not your federal return. If you worked in multiple states, you may receive multiple W2 forms and will need to file in each state where you earned income.

What to Do If Your W2 Contains an Error

If the numbers on your W2 do not match your records — for example, if the gross income is wrong or taxes withheld are incorrect — contact your employer's payroll or human resources department immediately. Do not assume the error will correct itself. Provide payroll with specific details about what is wrong and ask them to issue a corrected W2, officially called a Form W2-c.

Your employer must send you a corrected W2-c before you file your tax return if possible. If you have already filed and then discover an error on your W2, you will need to file an amended return using Form 1040-X. Keep copies of all correspondence with your employer about the error in case the IRS asks questions later.

Timing: When You Receive Your W2 and When to File

Employers must send W2 forms to employees by January 31 each year for the previous calendar year. The IRS also receives a copy. You should receive your W2 in the mail or through your employer's online portal by this date. If you do not receive it by early February, contact payroll and ask them to resend it or confirm they have your correct mailing address.

You can file your tax return as soon as you have your W2 in hand, which is typically late January or early February. The IRS begins processing returns in mid-January, though refunds may not be issued until mid-February or later depending on processing time and whether you file electronically or by paper.

Keeping Records and Storing Your W2

Save your W2 forms for at least three years. The IRS can audit tax returns filed within three years of the filing date, and you will need your W2 to prove the income and taxes reported. If you are applying for a loan, mortgage, or rental housing, you may also need to show your W2 as proof of income, so keeping copies is practical beyond tax time.

Store W2 forms with your other tax documents — either in a folder with your tax return and receipts, or digitally if you scan them. If you file electronically, your tax software may store a copy of your return, but keep the original W2 itself separate. If your employer offers online access to past W2s, you can also retrieve copies from there if you lose the paper version.

Frequently Asked Questions

Can I file my tax return before I receive my W2?

No. You need the actual numbers from your W2 to file accurately. If your employer is late sending it, contact payroll and ask for the information. You can file as soon as you have it, even if it arrives after January 31.

What if I worked for multiple employers in one year?

You will receive a separate W2 from each employer. You enter the Box 1 amount from each W2 on your tax return. Tax software will add them together automatically. Make sure you report all W2s — the IRS receives copies from each employer.

Do I need to mail my W2 to the IRS?

No. Your employer sends a copy to the IRS separately. You keep your copy and use it to file your return. You do not send the W2 itself to the IRS unless they specifically request it during an audit.

What does it mean if Box 2 shows zero federal tax withheld?

It means no federal income tax was taken from your paychecks. This can happen if you claimed exemptions on your W4 form or earned below the threshold for withholding. You may owe taxes when you file, or you may still receive a refund depending on your total income and deductions.

Can I get a copy of my W2 if I lost it?

Yes. Contact your employer's payroll department and ask for a duplicate. If your employer is no longer in business, you can request a transcript from the IRS that shows the W2 information they received. Call the IRS at 1-800-829-1040 or visit irs.gov.