Patricia's answer didn't help me, but is a very good explanation for those wishing to split state sales taxes between states. Mine was of mixing one state's income tax with another state's sales tax. The answer has repeatedly been 'no' but no one has explained why to what otherwise appears to be common sense: reside in one state,one set of rules; reside in another, another set of rules and then just pro-rate the year.
I did get an explanation today, outside this forum. It is more than plausible that a resident of a non-income tax state, e.g., FL, would be earning wages in another state and having those wages taxed in that different state. Example: a Jacksonville, FL resident works in Chicago, IL 3 days/week (long commute) and thus pays IL non-resident income tax. His Federal return can't reflect the mix of IL's [non-resident] income tax and FL's sales tax. As there is no way to distinguish that person from someone who moves mid-year from one type of state to another -- they could have changed residences, but not jobs -- and to stay in compliance with the tax code, the rule is one or the other in a given year.
