For 2024 taxes (prepared and to be filed in 2025), you may have to file MFS for both Federal and MO state taxes....in order for his income to not be taxed by MO.
MO seems to require filing the same status for MO as you use on a Federal tax return.
Some states allow filing MFJ Federal and MFS state, But in digging thru MO forms and instructions, I haven't seen anywhere that MO allows that.
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But I'm not particularly experienced with MO tax rules..., perhaps @robtm could help here if he is around in this Forum now (this late in the tax season, some Champs take a break), but he apparently knows MO rules better.
____________*Answers are correct to the best of my knowledge when posted, but should not be considered to be legal or official tax advice.*
