You'll have to define your place of actual Domicile during 2020.
Did live in a home with the spouse in SC, but work only temporarily in WA (like a summer job), then return to SC?
Or , did you live in one state...then move to the other where you expect to stay for the foreseeable future (which way, and which states....from....to...?)
OR, are you in the military, and HOR is SC ?
details..details..details...
____________*Answers are correct to the best of my knowledge when posted, but should not be considered to be legal or official tax advice.*
