2023 MT Instructions for doing so are on page 5 of the MT form 2:
"Montana law does not require you to claim the same filing status that you claimed on your Federal tax return. For example, if you are married and you filed your Federal tax return jointly, you and your spouse have the option to file your Montana tax return either jointly or separately."
But they also indicate that will go away for 2024 taxes, and require taxpayers to file using the same status as on their Federal tax return.
____________*Answers are correct to the best of my knowledge when posted, but should not be considered to be legal or official tax advice.*
