So you work in multiple states. How do you file your income taxes? If you are a resident in one state an perform work and earn income in another state you are requiered to file an income tax return for each state in which you work. If you are a resident of the state as determined by state law you file a resident tax return in that state, and yes you can be a resident in multiple states. For the states in which you are not a resident you file a non resident tax return. You will receive credit in your resident state for taxes you pay in non-resident states.
Take a professional athelete as an example. They are required to file a resident tax return in the state in which they are determined to be a resident, and a separate non-resident tax return for each state in which they play an away game. You can see how complicated this can get. Especially, for a professional athelete.