Where Are State Taxes on a W-2? Boxes 15-17

State tax information on a W-2 appears in Boxes 15 through 17, in the narrow band running across the bottom of the form. Box 15 shows the state and your employer’s state tax ID number, Box 16 shows the wages taxable by that state, and Box 17 shows the state income tax your employer withheld. Boxes 18 through 20 handle local taxes in the same row.

Where to Look on the Form

Federal information fills the larger boxes across the top and middle of the W-2. State and local data sits in the last row at the bottom, spread across Boxes 15 through 20.¹ The layout is the same whether you have a paper copy or view the form through a payroll portal. Look for the thin-lined boxes just below the Social Security and Medicare sections.

The state and local area has room for two rows, separated by a broken line. Each row can carry data for a different state or locality, so one W-2 can report earnings from up to two states.¹

Box 15: State and Employer State ID Number

Box 15 holds two pieces of information side by side: a two-letter state abbreviation and your employer’s state-assigned identification number. The abbreviation tells you which state’s tax authority received the withholding. The ID number is assigned by that state’s revenue department and is usually different from the federal Employer Identification Number in Box B near the top of the form.²

You’ll need the employer’s state ID when you file your state return. If it’s missing or illegible, the state may not be able to match your withholding to the right employer account, which can delay a refund or trigger a notice. Ask your employer’s payroll department for the correct number before filing.

Box 16: State Wages and Tips

Box 16 shows the portion of your pay that was taxable under the laws of the state named in Box 15. For most people who live and work in a single state, Box 16 matches Box 1 (federal taxable wages) exactly. When the two differ, it’s almost always because the state treats a particular type of income or deduction differently than the federal government does.¹

Common reasons for a mismatch:

Some states tax 401(k) or 403(b) contributions that the federal government lets you defer. When the state doesn’t recognize the deferral, Box 16 comes in higher than Box 1.
Certain pre-tax commuter or parking benefits reduce federal wages but may not reduce state wages, pushing Box 16 above Box 1.
If you earned income in more than one state, Box 16 reflects only the wages allocated to the state on that row. Add the state lines together and the total should come close to your overall earnings.

A mismatch by itself isn’t a red flag. Just make sure you enter the Box 16 figure on your state return rather than copying Box 1, because the state’s tax calculation starts from that number.

Box 17: State Income Tax Withheld

Box 17 is the dollar amount your employer sent to the state tax agency on your behalf over the year. On your state return, you compare the tax you actually owe against the amount in Box 17. If the withholding exceeds your liability, you get a refund. If it falls short, you owe the difference.

Box 17 ties directly to the state code in Box 15. When a W-2 reports two states, each row has its own Box 17, and each amount applies only to the state on that row.¹ Crossing wires between the two rows is one of the most common mistakes on multi-state returns, and it usually shows up as one state claiming you underpaid while the other issues an unexpected refund.

When Boxes 15 Through 17 Are Blank

Empty state boxes don’t automatically mean something is wrong. Nine states have no state income tax: Alaska, Florida, Nevada, New Hampshire, South Dakota, Tennessee, Texas, Washington, and Wyoming. If you worked exclusively in one of them, your employer had nothing to withhold and nothing to report, so Boxes 15 through 17 will be blank. You won’t need to file a state income tax return there, and you can skip these boxes when entering your W-2 into tax software.

Blank boxes are a problem if you worked in a state that does impose an income tax. That points to a payroll error. Check your pay stubs to see whether state taxes were deducted throughout the year. If they were but the W-2 doesn’t reflect them, ask your employer for a corrected form.

Why State Programs May Appear in Box 14 Instead

Some state-mandated payroll deductions look like taxes but aren’t income taxes, so they belong in Box 14 rather than Box 17. State disability insurance is the most common example. California and New Jersey both require employers to report disability tax withholding in Box 14, often labeled “CA SDI” or “NJ SDI.” If that amount lands in Box 17 by mistake, your state tax credits can be denied.

Washington requires employers to show the employee’s share of Paid Family Leave in Box 14 as well, and other states use Box 14 for similar programs. The distinction is straightforward: Box 17 is strictly for state income tax. Everything else goes in Box 14, even when the deduction was mandatory and went to a state agency.

Boxes 18 Through 20: Local Taxes

Boxes 18, 19, and 20 mirror the state boxes but cover local jurisdictions like cities and counties. Box 18 shows wages subject to local income tax, Box 19 shows the local tax withheld, and Box 20 names the locality. Not everyone will see entries here. Local income taxes exist in parts of a few states, but most areas of the country don’t impose them.

If you do have local withholding, you’ll typically need to file a separate local return or include the figures on your state return, depending on the jurisdiction. The locality name in Box 20 tells you where to send that filing.

Working in More Than One State

If you earned wages in two states during the year, both states fit on a single W-2 in the two rows provided across Boxes 15 through 20. Each row runs on its own state abbreviation, wage figure, and withholding amount. If you worked in three or more states, your employer has to issue a second W-2 to cover the additional states.¹ Gather every W-2 before filing so each state gets its required return.

Reciprocity can also affect what shows up in Box 15. About 16 states and the District of Columbia have reciprocal tax agreements with neighboring states. Under those agreements, an employer withholds only for your home state when you commute across a participating border, and Box 15 will show your home state rather than the state where you physically worked. If your employer doesn’t have a reciprocity certificate on file for you, they’ll withhold for the work state by default, and you’ll need to sort it out on your returns.

Fixing Errors in the State Boxes

Mistakes in the state boxes happen more often than you’d expect, particularly at companies with employees spread across states. Start by contacting your employer’s payroll department and asking for a correction. Employers issue corrections on Form W-2c, and the IRS expects them to provide corrected forms as soon as they discover the error.³

For the 2026 tax year, employers must furnish your W-2 by February 1, 2027.⁴ If you’ve requested a correction and your employer won’t cooperate or has gone out of business, you can file Form 4852 as a substitute for the W-2.⁵ You’ll estimate wages and withholding from your pay stubs and keep records of every attempt you made to get the correct W-2. If a corrected form later changes the numbers, file an amended state return to reconcile.

1
Internal Revenue Service. General Instructions for Forms W-2 and W-3 (2026) – Section: Boxes 15 Through 20
2
Internal Revenue Service. General Instructions for Forms W-2 and W-3 (2026) – Section: Box 15
3
Social Security Administration. Helpful Hints to Forms W-2c/W-3c Filing
4
Internal Revenue Service. 2026 General Instructions for Forms W-2 and W-3
5
Internal Revenue Service. About Form 4852, Substitute for Form W-2, Wage and Tax Statement