What Is the State Identification Number on a 1099?

The state identification number on a 1099 sits in Box 6 of Form 1099-NEC and in Box 17 of Form 1099-MISC, both labeled “State/Payer’s state no.” It’s the payer’s registration number with a state tax agency, not yours, and it shares its box with the two-letter state abbreviation, so the field typically reads something like “CA 123-4567-8.”¹

The two forms use different box numbers for the same information, which is where most of the confusion starts.

Where To Find It on Form 1099-NEC

On the 1099-NEC, the state information section runs across Boxes 5 through 7 at the very bottom of the form:

Box 5 shows state income tax withheld from your payment.
Box 6 shows the state abbreviation and the payer’s state ID number.
Box 7 shows the amount of the payment subject to that state’s income tax.

Box 6 is the one you’re looking for.¹

Where To Find It on Form 1099-MISC

On the 1099-MISC, the same information lives in Boxes 16 through 18:

Box 16 shows state income tax withheld.
Box 17 shows the state abbreviation and the payer’s state ID number.
Box 18 shows the amount of the state payment.

Box 17 is the state ID field.¹

When Two States Appear on One Form

Both forms include a dashed line splitting the state section in half, which allows reporting for up to two states on a single copy. If you earned income in two states from the same payer, each side of the split will show its own state abbreviation, state ID, withholding amount, and state income figure. Payers reporting for more than two states file an additional 1099.

What the Number Actually Is

The state identification number is a code a state tax agency assigns to a business when it registers for tax purposes. It functions as the state-level counterpart to the federal Employer Identification Number that appears near the top of the form. The state’s Department of Revenue, Department of Taxation, or equivalent agency uses this number to match the income on your 1099 against the payer’s account in state records.

The number belongs to the payer, not the recipient. If you’re a contractor who received the form, you don’t need a state ID of your own to file your return; the field identifies the business that paid you.

Format varies from state to state. Some states issue a unique registration number that looks nothing like a federal EIN. Others let the payer use the federal EIN as the state ID, sometimes with a suffix appended. That inconsistency is a big part of why the field causes trouble.

When the Box Is Blank

A blank state ID field doesn’t automatically mean the form is wrong. The IRS instructions state that the state information boxes “are provided for your convenience only and need not be completed for the IRS.”¹ The payer completes them for state reporting, not federal.

A few situations commonly produce an empty state ID box:

No state income tax applies. Nine states don’t tax earned income, so there’s no state agency to report to.
The payer didn’t withhold state income tax and skipped the state section.
The payer simply overlooked the field.

An empty box usually won’t block you from filing your state return. You report the income to your state regardless of whether the payer filled in the state section. If you believe state tax was actually withheld but the form doesn’t show it, ask the payer for a corrected 1099. If the payer doesn’t respond, you can call the IRS at 800-829-1040 and the IRS will contact the payer on your behalf.²

If the State ID Number Is Wrong

Errors in the state section are common, especially when a business is registered in many states. What you do next depends on which side of the transaction you’re on.

If you received the form and the state ID looks wrong, contact the payer and request a corrected 1099. This isn’t something you fix on your own return; the correction has to come from the payer.

If you’re the payer and the mistake is limited to the state information boxes, a corrected federal filing isn’t required, because those boxes aren’t used by the IRS.¹ You do need to correct the information with the state tax agency that actually uses the number, and each state has its own procedure for that. Contact the state’s Department of Revenue for instructions.

What Payers Should Know About the Number

Payers receive a state identification number when they register with a state’s tax authority, generally through a business tax application filed with the Department of Revenue or equivalent agency. A business operating in multiple states needs a separate registration in each state where it has a reporting obligation, and each state’s number may follow a different format.

If you’re a payer and can’t locate the number for a given state, check your original state registration paperwork or any prior withholding return filed with that state. The state tax agency can also provide it directly if you contact them.

For payers issuing 1099s across many states, keeping a clean master list of every state ID is worth the effort. Putting one state’s number on a form meant for another, or leaving the field blank when the state requires it, can trigger rejections in the state’s automated processing, and untangling a state-level error is often harder than fixing a federal one because each state runs its own correction process.

What This Number Means for Your Own Return

If you’re reviewing a 1099 you received, the state ID number itself is mostly informational. It tells the state which registered business paid you, and the state uses it internally to match records. The figures that actually drive your state tax return are the state income amount and the state tax withheld, in Boxes 5 and 7 on a 1099-NEC or Boxes 16 and 18 on a 1099-MISC. Those are the numbers to transcribe carefully; the state ID is there for the state’s benefit, not yours.

1
Internal Revenue Service. Instructions for Forms 1099-MISC and 1099-NEC
2
Internal Revenue Service. What to Do When a W-2 or Form 1099 Is Missing or Incorrect