Running payroll for employees in more than one state means registering with each state’s tax and labor agencies where those employees actually work, withholding under that state’s rules, paying its unemployment tax, deducting for any disability or paid-leave programs it runs, and filing the quarterly and year-end returns each agency requires. Multi-state payroll tax compliance is not one process repeated across borders. It is a separate compliance regime in every jurisdiction, and the agencies rarely coordinate, so a mistake in one state does not surface in another until a penalty notice arrives.
The work breaks into a few decisions: figuring out which states you owe anything to, applying the exceptions that can shift the answer, opening the right accounts, and then keeping the filings on schedule.
Which States You Owe
Start by taking the no-tax states off the withholding list. Alaska, Florida, Nevada, South Dakota, Tennessee, Texas, and Wyoming have no individual income tax. New Hampshire taxes interest and dividends but not wages. Washington imposes no broad-based income tax, though it does tax certain capital gains above a high threshold. An employee working exclusively in any of these states means no state income tax withholding to run.
That is only the withholding piece. Unemployment insurance still applies. Texas still requires unemployment registration and quarterly wage reporting. Florida still assesses a reemployment tax on employers. The disability and paid-leave layer described below can apply too, depending on the state.
For the roughly 40 states that do tax wages, the trigger is nexus. Physical nexus is the common form for payroll: an office, warehouse, inventory, or an employee physically working inside the state. Economic nexus, which turns on revenue or transaction thresholds, matters more for sales tax than for payroll. Once physical nexus exists, the obligation follows automatically. Register for a withholding account, deduct state income tax from affected paychecks, and remit on that state’s schedule. Where the company is headquartered is irrelevant. A Delaware entity with its main office in Texas still owes New York withholding for an employee who reports to a New York office.
The Exceptions That Change the Answer
Reciprocity Agreements
About 16 states and the District of Columbia participate in reciprocal agreements that let an employee pay income tax only to the state where they live, even when they commute across a border. The employer withholds for the residence state and skips the work state.
The mid-Atlantic cluster is the most familiar. Virginia’s Form VA-4 lets residents of Maryland, Pennsylvania, West Virginia, Kentucky, and the District of Columbia working in Virginia opt out of Virginia withholding.1Virginia Department of Taxation. Form VA-4 – Employee’s Virginia Income Tax Withholding Exemption Certificate Maryland’s Form MW507 is the mirror image for residents of Virginia, West Virginia, Pennsylvania, and D.C. working in Maryland.2Maryland Comptroller. Maryland Form MW507 – Employee’s Maryland Withholding Exemption Certificate Similar agreements exist in the Midwest between Illinois and its neighbors and across the Ohio, Indiana, and West Virginia corridor.
Reciprocity works only when the employee files the correct exemption certificate. Without that form, you are legally required to withhold for the work state. Collect the certificate at onboarding, before the first check goes out.
The Convenience of the Employer Rule
A few states ignore where a remote employee physically sits. Under a convenience-of-the-employer test, working from home because you choose to rather than because the employer requires it means the wages are still taxed as if the employee were at the office. New York enforces this most aggressively. New Jersey adopted its own version in recent years for nonresidents whose home states impose a similar test. Delaware and Nebraska have comparable provisions. Hiring a remote worker who lives in a different state from your office does not necessarily mean you can ignore the office state’s withholding.
De Minimis Thresholds
Not every business trip triggers withholding. Many states set a minimum number of days or income before nonresident withholding kicks in. Some give a cushion of 30 or 60 days. Others require withholding from the first day an employee performs work inside their borders. A few layer both a day count and an income floor, requiring both to be exceeded. For employees who travel regularly, tracking running day and income totals in each state is the only reliable way to catch a registration deadline before it passes. No uniform federal threshold exists, so each state’s rule has to be checked on its own.
Registering for State Accounts
Once withholding is required, open an account with the state’s tax agency. Nearly every state handles this through an online portal, and processing typically takes one to three weeks before the withholding account number is issued. Some states charge a small registration fee. Keep the confirmation number from every submission. The state-issued withholding ID has to appear on every future return and deposit.
State applications ask for repetitive information, so assemble it once. You will need:
- Your Federal Employer Identification Number.3Internal Revenue Service. Employer Identification Number
- The legal business name exactly as filed with the Secretary of State.
- Entity type (C-corp, S-corp, LLC, partnership, or sole proprietorship). Picking the wrong classification can stall the application or produce incorrect tax rates.
- Physical address of each work location in the state, plus each employee’s home address and the date they first earned wages there. An inaccurate start date is one of the more common causes of late-filing penalties.
- The NAICS code for your primary business activity. States use it for reporting and, in some cases, to assign industry-based unemployment insurance rates.
- Projected annual payroll. This drives your deposit frequency. High-volume employers may have to deposit semi-weekly, while smaller operations file monthly or quarterly.
- An authorized contact. Naming a payroll provider or PEO here can simplify ongoing correspondence.
Some states also want a copy of the corporate charter or a certificate of authority proving you can conduct business there. Having digital copies of formation documents ready before you start the first state saves time on every one after it.
State Unemployment Insurance
Unemployment registration is a separate obligation from withholding, often handled by a different agency. A Department of Labor, Workforce Commission, or Employment Security agency typically runs unemployment accounts, not the revenue department that handles withholding. Much of the underlying business data is the same, but the tax works differently.
New employers are assigned a default rate because they have no layoff history yet. Starting rates for 2026 range from about 1% in states like Delaware, Idaho, and North Carolina to above 4% in New York, with construction employers often facing higher initial rates.4Internal Revenue Service. Understanding Employment Taxes After a few years, the state recalculates based on claims filed against your account. Low turnover pulls the rate down; frequent layoffs push it up.
The taxable wage base varies dramatically. Some states tax only the first $7,000 of annual wages, matching the federal floor. Others set the ceiling above $60,000. The same employee can cost ten times more in unemployment tax in a high-base state. Quarterly wage reports are typically due by the last day of the month following the close of the quarter, and a missed filing (even one showing zero wages) can trigger a flat-fee penalty.
How FUTA Ties In
The Federal Unemployment Tax Act imposes a 6.0% tax on the first $7,000 of each employee’s wages, paid entirely by the employer with nothing deducted from paychecks.5Office of the Law Revision Counsel. 26 USC 3306 – Definitions The IRS allows a credit of up to 5.4% for state unemployment taxes paid on time, dropping the effective FUTA rate to 0.6% in most cases.6U.S. Department of Labor. FUTA Credit Reductions – Unemployment Insurance
When a state borrows from the federal government to cover its unemployment trust fund and fails to repay within two years, employers in that state lose part of the 5.4% credit. Their effective FUTA rate climbs above 0.6%. The list of credit-reduction states is announced annually and can shift year to year. If you operate in multiple states, check the list each year, because the added cost applies per employee and adds up quickly.
Disability, Paid Leave, and Local Taxes
Income tax and unemployment do not exhaust the payroll picture. Five states and Puerto Rico require temporary disability insurance: California, Hawaii, New Jersey, New York, and Rhode Island. Costs are typically split between employer and employee contributions through payroll deductions.
More than a dozen states and the District of Columbia now mandate paid family and medical leave programs funded through payroll contributions. California, Colorado, Connecticut, Delaware, Maine, Maryland, Massachusetts, Minnesota, New Jersey, Oregon, Rhode Island, and Washington all run state-administered programs using pooled payroll taxes. New York runs a similar program through a mandatory private insurance model. Each program sets its own contribution rate, wage cap, and benefit level. New Jersey’s 2026 family leave insurance contribution, for example, is 0.23% on the first $171,100 in covered wages.
The practical result: two states rarely impose the same set of deductions. An employee in California may owe SDI contributions that an employee in Texas does not. An employee in Washington may owe paid family leave premiums that an employee in Florida does not. Each program requires its own registration, its own reporting schedule, and its own line on the pay stub. A compliance checklist limited to withholding and unemployment will miss these.
Local taxes sit on top of all of it. Hundreds of cities and counties impose payroll or income taxes administered by local agencies rather than state departments. Ohio has more than 800 municipal taxing jurisdictions. Pennsylvania has an earned income tax levied by nearly every municipality, with Philadelphia’s rate approaching 4%. Kentucky, Indiana, and Maryland assess local income taxes at the county or city level. Outside those states, cities like New York City, Detroit, St. Louis, Kansas City, and several in Alabama impose separate local income taxes ranging from under 1% to over 3%. A few Colorado cities charge flat monthly occupational taxes. Before you run the first payroll in a city where you have not operated before, check for local obligations.
Supplemental Pay and Year-End Reporting
Regular wages source cleanly to where the work happened. Bonuses, commissions, and equity compensation are harder when the employee split time between states during the period the payment covers. Most states expect supplemental pay to be allocated in proportion to days worked in each state during the relevant period. A year-end bonus covering a year split 60/40 between two states is split the same way.
Many states also set flat supplemental withholding rates that differ from the graduated rates used on regular wages. Using the wrong rate is a routine payroll error. For a large commission tied to a single transaction, the sourcing question is where the services producing that commission were performed, not where the customer sat. Getting it wrong overpays one state and underpays another, generating a refund claim on one side and a deficiency notice on the other.
At year end, W-2 Boxes 15 through 17 report each state’s data separately. Box 15 lists the state abbreviation and your withholding account number. Box 16 shows the wages subject to that state’s tax. Box 17 shows the amount withheld. Each state gets its own line, and the Box 16 amounts should normally add up to the federal wage figure in Box 1.
New York is the exception. Rather than reporting only wages earned in-state, New York requires employers to enter the total federal Box 1 wages on its Box 16 line. The employee handles the allocation on the nonresident return. So a W-2 covering both New York and another state can show Box 16 totals that exceed Box 1. That looks wrong and is correct.
Most states also require annual reconciliation returns tying W-2 data to the quarterly withholding reports filed during the year. Deadlines vary but commonly fall on January 31 or the end of February. Missing a reconciliation is a separate penalty from missing a quarterly filing, and multi-state employers can easily lose track of what is due when.
When to Hand It Off
By the third or fourth state, the registration and filing workload can outpace an internal team. A Professional Employer Organization enters into a co-employment arrangement and takes over state registrations, quarterly filings, rate monitoring, and deposit remittances. In many states, the PEO files under its own accounts, so the client does not register separately in each jurisdiction. Multi-state payroll software is a lighter-touch alternative. It applies state-specific withholding tables, tracks de minimis day counts for traveling employees, and flags when a new registration is required.
Neither option removes the employer’s underlying liability. If a PEO fails to remit taxes, the client company is still on the hook. For most small and mid-size businesses, the cost of a provider is far less than the penalties and professional fees that follow a compliance failure spread across several states.