Your employer’s EIN on a W-2 is the nine-digit number printed in Box b, labeled “Employer’s identification number,” formatted with a hyphen after the first two digits (for example, 12-3456789). Box b sits on the left side of the form, just below Box a and directly above your employer’s name and address in Box c.1Internal Revenue Service. General Instructions for Forms W-2 and W-3 (2026)
The number should be the same on every copy you receive. You get three: Copy B for your federal return, Copy 2 for state and local filings, and Copy C for your records. Box b reads identically on all of them. It also stays the same from year to year for the same employer, because the EIN is what the business uses on its federal employment tax returns.
Don’t Mix It Up With the Other Numbers on the Form
Three numbers cluster together on a W-2, and only one of them is the EIN.
- Box a is an optional control number your employer’s payroll system assigns internally. It has nothing to do with the IRS.
- Box d is your own Social Security number.
- Box 15, farther down the form, holds your employer’s state ID number. That one is assigned by the state, not the IRS, and it exists only for state and local tax reporting.1Internal Revenue Service. General Instructions for Forms W-2 and W-3 (2026)
When your federal return or tax software asks for the “employer identification number” or “EIN,” it wants Box b. When a state form asks for the employer’s state ID, it wants Box 15. Copying the state ID into the federal EIN field is one of the most common W-2 entry errors, and it will hold up your return.
If Box B Is Blank, Smudged, or Your W-2 Hasn’t Arrived
You can usually find the EIN on documents you already have:
- Last year’s W-2 or the Form 1040 you attached it to. Unless the employer restructured or changed entities, the number is the same.
- Your pay stubs. Many payroll systems print the federal EIN in the employer information block at the top of every pay statement.
- Any other tax form the same employer issued you, such as a 1099.
If none of those help, you can request a Wage and Income Transcript from the IRS. The transcript shows what was reported on information returns like the W-2, though it doesn’t include state or local data.2Internal Revenue Service. Topic No. 159, How to Get a Wage and Income Transcript Pull it through your IRS online account or by mailing Form 4506-T. Data for the most recent tax year often isn’t available until mid-year, so this route works best for verifying a prior year.
Why the Right EIN Matters
The IRS and Social Security Administration use the EIN to match what you report against what your employer reported.3Internal Revenue Service. Employer Identification Number When the numbers don’t line up, the return gets pulled for manual review, which can delay a refund by weeks. A wrong digit in Box b, or the Box 15 number entered by mistake, is enough to trigger that.
Fixing a Wrong or Missing EIN
Contact your employer’s payroll or HR department as soon as you notice the problem. The employer is responsible for issuing a corrected W-2, Form W-2c, and filing it with the SSA.1Internal Revenue Service. General Instructions for Forms W-2 and W-3 (2026) Ask for a specific timeline. A simple EIN correction usually takes only a few days once the request reaches the right person.
If the Corrected Form Doesn’t Come
If you’ve asked your employer and still don’t have a corrected W-2 by the end of February, call the IRS at 800-829-1040. Have this information ready:
- Your name, address, phone number, and Social Security number
- The dates you worked for the employer
- The employer’s name, address, and phone number
The IRS will send the employer a letter demanding a corrected W-2 within ten days and will mail you a copy of Form 4852 with instructions.4Internal Revenue Service. W-2 – Additional, Incorrect, Lost, Non-Receipt, Omitted
Filing With Form 4852
If the filing deadline is close and you still don’t have a correct W-2, you can file using Form 4852, Substitute for Form W-2.5Internal Revenue Service. About Form 4852, Substitute for Form W-2, Wage and Tax Statement The form lets you estimate wages and withholding from your pay stubs. Be as precise as you can, because the IRS gives Form 4852 filings extra scrutiny. If the corrected W-2 arrives later and the numbers differ from your estimate, file Form 1040-X to reconcile the difference.6Internal Revenue Service. What to Do When a W-2 or Form 1099 Is Missing or Incorrect