The line labeled “SIT withheld” on your paycheck is the state income tax your employer deducted from that pay period and will send to your state’s tax agency on your behalf. SIT stands for State Income Tax, and “withheld” means it came out before the money hit your account. It sits on your stub next to federal withholding, Social Security, and Medicare, and every dollar of it gets reported at year-end in Box 17 of your W-2 and credited against whatever you actually owe your state.
Why the Deduction Exists
Most states that tax wages require employers to pull an estimated amount of state income tax from each paycheck and forward it to the state’s department of revenue. The system mirrors federal income tax withholding: rather than facing one large state tax bill in April, you pay it gradually across the year. Your employer runs the math, makes the deduction, and remits the money for you.
Both sides benefit from the pay-as-you-go setup. You avoid a surprise balance due at filing time, and the state gets a predictable flow of revenue. The amount pulled each pay period is only an estimate, though. How close it lands to your real tax liability depends on the inputs you gave your employer and the state’s rate structure.
What Sets the Dollar Amount
Two things drive the SIT figure on your stub: the information you put on a withholding form, and your gross pay for that period. Most states use their own version of the federal W-4 where you declare filing status, dependents, and any extra amount you want withheld. A handful of states let employers pull that information directly from your federal W-4 instead.
Filing status does the heaviest lifting. Choosing “Married” with several dependents tells payroll to withhold less from each check, because the system assumes more of your income will be offset by deductions and exemptions. Choosing “Single” with no dependents triggers the highest withholding rate per dollar earned.
Your gross pay is the other half. Your employer runs your earnings through the state’s published withholding tables or formulas, which bake in the marginal brackets. In a state with graduated rates, the first slice of income might be withheld at 2%, while income above a higher threshold is withheld at 5% or 6%. Other states keep it simple with a flat rate. Pennsylvania, for example, applies 3.07% to all taxable wages regardless of income level.
Rates themselves vary widely across the country. A few states with graduated brackets top out above 10% for their highest earners, while flat-rate states charge the same percentage at every level. Brackets and rates change periodically, so your state’s department of revenue website is the place to confirm current figures.
When You’ll See $0 for SIT
Nine states don’t impose an income tax on wages, so paychecks there show $0 for SIT withheld:
- Alaska
- Florida
- Nevada
- New Hampshire
- South Dakota
- Tennessee
- Texas
- Washington
- Wyoming
New Hampshire historically taxed interest and dividend income but not wages; that tax was fully phased out as of 2025, so residents now face no state income tax on any type of income. Washington has no traditional wage income tax either, though it does impose a separate capital gains tax on certain high-value investment sales.
A $0 SIT line doesn’t mean your stub is free of all state-level deductions. Some jurisdictions require withholding for state disability insurance or paid family leave programs. In states like Ohio and Pennsylvania, hundreds of cities and school districts levy their own local income taxes that show up as separate line items. Those local withholdings are distinct from SIT and governed by local rules.
Changing How Much Is Withheld
You can submit a new state withholding form to your employer at any time, and there’s no limit on how often you can change it. If you get a large state refund every spring, you’ve essentially been lending money to the state for free; increasing your allowances or reducing any extra withholding would put more cash in each check. If you owe the state every year, dialing withholding up avoids the annual sting.
Certain life events are good triggers for a review: marriage or divorce, a new child, a second job, or a jump in income. Any of these can push your real tax liability far enough from your current withholding to create either a big refund or a balance due. For federal withholding, employers must implement a revised W-4 no later than the start of the first payroll period ending on or after 30 days from receiving the form. State timelines vary, but most payroll systems apply the change within one or two pay cycles.
Most states offer online withholding calculators where you plug in income, filing status, and deductions to see roughly how much should come out of each check. Running that calculator after you file your state return each year is the easiest way to keep withholding dialed in.
When You Live in One State and Work in Another
If your home and your job sit in different states, both can potentially claim the right to tax the same wages. States prevent that double hit through either reciprocity agreements or tax credits, and the result shows up on your pay stub as SIT withholding for one state or the other.
Reciprocity Agreements
Some pairs of neighboring states have reciprocal agreements that let you pay income tax only to your home state, even though your wages are earned elsewhere. When one applies, your employer withholds SIT only for your state of residence and ignores the work state. You usually need to file a withholding exemption form with your employer to turn this on; without it, payroll may default to withholding for the work state, leaving you to sort it out at filing.
These agreements cluster in the Midwest, Mid-Atlantic, and D.C.-area regions. Not every bordering-state pair has one, so check with your employer or your home state’s revenue department if you commute across a line.
No Agreement in Place
Without reciprocity, your employer typically withholds SIT for the state where you physically work. You then file a nonresident return in the work state and a resident return at home. Most home states offer a credit for taxes paid to the work state to prevent double taxation, and the credit generally equals the lesser of what you actually paid the other state or what your home state would have charged on the same income.
Remote Work and the Convenience Rule
Remote arrangements have created a wrinkle that catches people off guard. A handful of states, including New York, apply what’s called a “convenience of the employer” rule. If you work remotely from your home state but your employer’s office is in New York, New York may tax your full wages as if you earned them there, unless the remote setup exists out of business necessity rather than personal convenience. Connecticut, Delaware, Nebraska, Oregon, and Pennsylvania have adopted variations. The practical effect is that your employer might withhold SIT for the office state even though you never set foot there, and your home state’s credit may not fully offset the extra tax.
How SIT Reconciles at Year-End
Everything your employer withheld for SIT during the year is totaled in Box 17 of your W-2, with your state-taxable wages shown in Box 16. The employer also sends a copy to the state tax authority. When you file your state return, you calculate your actual liability by applying the state’s rates, deductions, and credits to your full-year income, then subtract Box 17. If your employer withheld more than you owe, the state refunds the difference. If too little came out, you pay the balance.
Landing close to zero is the goal: no large refund, no large balance due. A consistently large refund means too much is being pulled from each check and could have been earning interest or covering bills throughout the year. A consistent balance due means your inputs need adjusting upward, and it can also trigger an underpayment penalty.
Most states penalize you when withholding and any estimated payments fall too far below actual liability. Thresholds vary, but many states follow a framework similar to the federal safe harbor: you generally avoid a penalty if total payments cover at least 90% of the current year’s tax or 100% of the prior year’s, whichever is less. Some states raise the prior-year figure to 110% for higher-income filers. Penalties typically run as interest on the underpaid amount for each quarter you fell short rather than as a flat fine. Fixing a shortfall in the fourth quarter means three quarters of interest have already accrued, so the practical move is to review withholding right after you file each year’s return.