From Publication 17
In general, your filing status depends on
whether you are considered unmarried or married.
Unmarried persons. You are considered unmarried for the whole year if, on the last day of
your tax year, you are either:
• Unmarried, or
• Legally separated from your spouse under
a divorce or separate maintenance decree.
State law governs whether you are married
or legally separated under a divorce or separate
maintenance decree.
Divorced persons. If you are divorced under a final decree by the last day of the year,
you are considered unmarried for the whole year
