What happens if I work in multiple states?

Working in multiple states generally requires filing a nonresident return in each state where you earned income, plus a resident return in your home state. Your home state usually provides a credit for taxes paid to other states, preventing full double taxation. Remote workers complicate this — some states claim the right to tax you based on where your employer is located (the "convenience of the employer" rule). Keep detailed records of days worked in each state.