What actually happens
An employee who lives in West Virginia and performs work in Maryland sits in two tax systems at once. The residence state claims the right to tax all of a resident's income wherever earned; the work state claims the right to tax income sourced within its borders. Maryland and West Virginia resolved that overlap by agreement: the work state gives up its claim on commuters' wages entirely.
The certificate is not optional
Reciprocity does not apply automatically because the employee's address is in West Virginia. It applies when the employee gives you a signed MW507 (Employee's Maryland Withholding Exemption Certificate (exemption claimed on the reciprocal-state line)). Until that form is in your hands you are required to withhold Maryland tax, and an auditor will ask to see it. The form stays in your records; it is not filed with the state.
Unemployment insurance goes to one state only
Income tax can be split between states. Unemployment insurance cannot. Under the localization test used by every state, an employee whose services are performed entirely in Maryland is covered by Maryland for unemployment purposes, and all wages are reported there — regardless of where they live, where you are headquartered, or which state's income tax you withhold. Maryland's 2026 taxable wage base is $8,500. The four-factor test in order.
Local taxes are a separate problem
Maryland: EVERY Maryland county and Baltimore City imposes a local income tax, collected together with the state tax through payroll withholding at combined state+local rates. Nonresidents working in Maryland who are not covered by reciprocity pay a special nonresident rate (state rate plus a statutory nonresident surcharge) in lieu of a county rate.
West Virginia: Several West Virginia municipalities (e.g., Charleston, Huntington, Parkersburg, Weirton) impose a flat per-week City Service Fee (roughly $2-$5 per week) on people who work in the city, withheld by employers. It is a flat head-fee, not a percentage-of-income tax, and is not covered by state reciprocity.
What you have to register for
| Obligation | State | Agency |
|---|---|---|
| Income tax withholding | West Virginia | West Virginia Tax Division |
| Unemployment insurance | Maryland | Maryland Department of Labor, Division of Unemployment Insurance |
Frequently asked
Do Maryland and West Virginia have a reciprocal tax agreement?
Yes. Maryland exempts West Virginia residents from Maryland income tax withholding on wages, provided the employee files MW507 with their employer. Without that form on file the employer must still withhold Maryland tax.
Which state's income tax should be withheld?
West Virginia. Under the agreement the wages are taxable only by the state of residence, so you withhold West Virginia tax and stop withholding Maryland tax once the certificate is filed.
Which state gets the unemployment insurance wages?
Maryland. Unemployment coverage is never split between states for a single job. The localization test assigns the whole job to the state where services are performed, which here is Maryland, regardless of residence or where the employer is headquartered.