The state payer’s state number is the identification number a state tax agency assigns to an employer or other payer so it can track state income tax withholding. On your W-2, it sits in Box 15, right next to your state’s two-letter abbreviation. On a 1099, it appears in the state information section. It functions like a federal EIN, but only at the state level, and each state issues its own version with its own format.1Internal Revenue Service. General Instructions for Forms W-2 and W-3 (2026)
What the Number Is For
When your employer withholds state income tax from your paycheck, that money has to make its way to the correct state agency and get credited to the right employer account. The state payer’s state number is how the state links the two. It’s separate from the federal EIN, and there’s no uniform format across states: one state might call it a State Employer ID Number, another a Withholding Account Number, and the length and structure vary.1Internal Revenue Service. General Instructions for Forms W-2 and W-3 (2026)
Where to Find It on Your W-2
Look at Box 15. It shows the two-letter state abbreviation on the left and the employer’s state ID number on the right. Boxes 15 through 20 hold all the state and local information on the form: Box 16 reports state wages, and Box 17 reports state income tax withheld.1Internal Revenue Service. General Instructions for Forms W-2 and W-3 (2026)
If you worked in more than one state during the year, Box 15 can hold entries for up to two states, separated by a broken line. When wages were earned in three or more states, your employer should issue a second W-2 for the additional states.1Internal Revenue Service. General Instructions for Forms W-2 and W-3 (2026) Each entry pairs a state abbreviation with its own employer state ID, state wages, and state tax withheld.
Not seeing the number on your W-2? Check a recent pay stub. Many employers print state withholding details on each stub, usually near the company information or inside a tax withholding breakdown. If it isn’t there either, contact your employer’s payroll or HR department and ask for it directly.
The Number on 1099 Forms
The same kind of identifier appears on 1099s when the payer withheld state tax. IRS instructions direct payers reporting state withholding to enter “the abbreviated name of the state and the payer’s state identification number” in the designated state information box.2Internal Revenue Service. Instructions for Forms 1099-MISC and 1099-NEC (04/2025)
The box number depends on the form. On Form 1099-NEC, it’s Box 6. On Form 1099-MISC, it’s Box 17. Other 1099 variants place it in their own state information section. The purpose is the same across forms: it lets the state match the withholding the payer sent in with the credit you claim on your return.
When Box 15 Is Blank
Nine states do not impose a state income tax on wages: Alaska, Florida, Nevada, New Hampshire, South Dakota, Tennessee, Texas, Washington, and Wyoming. If you worked only in one of those states, Box 15 will typically be empty because there’s no state withholding to report and no state account number to list. No state income tax means no state withholding ID.
If you earned wages in both a taxing state and a no-tax state during the same year, only the taxing state’s information will appear in Boxes 15 through 17.
Why It Matters When You File
When you file a state income tax return, the state uses the payer’s state number to match the withholding your employer remitted with the withholding you’re claiming as a credit. If the number is wrong or missing, the state may not be able to confirm the taxes were paid in on your behalf. The usual result is a delayed refund or a letter from the state asking you to verify your withholding.
Most state tax return software and paper forms include a field for this number. Entering it correctly the first time keeps your return from getting flagged for manual review.
What to Do If the Number Is Missing or Wrong
Start with your employer’s payroll or HR department. Explain what’s missing or incorrect and ask for a correction. Employers issue corrections on Form W-2c, the Corrected Wage and Tax Statement, which the Social Security Administration says should be filed “as soon as possible after you discover an error.”3Social Security Administration. Helpful Hints to Forms W-2c/W-3c Filing A W-2c can fix any field on the original W-2, including the state identification information in Box 15.4Internal Revenue Service. About Form W-2 C, Corrected Wage and Tax Statements
If your employer is unresponsive, has gone out of business, or won’t issue a corrected form, you can file Form 4852 as a substitute for a missing or incorrect W-2.5Internal Revenue Service. About Form 4852, Substitute for Form W-2, Wage and Tax Statement, or Form 1099-R You estimate your wages and withholding from the best records you have. A year-end pay stub with year-to-date totals works well. The IRS also notes that if you had the same employer the prior year and your pay stayed essentially the same, a prior-year W-2 can serve as the basis for your estimates.6Internal Revenue Service. Using Form 4852 When Missing the Form W-2 or 1099-R
Form 4852 requires you to explain what steps you took to get the missing or corrected form, so document your attempts to reach the employer. Filing with careful estimates is better than missing your filing deadline while you wait.