If you were still legally married as of the end of 2016, your best option would be to file as married filing jointly because you will have the lowest tax rate, the highest standard deduction, and likely more tax benefits. If you were legally separated then you would need to file as single. If you have children or other dependents, you might qualify for head of household status. However the rules for filing head of household are different depending on whether or not you are married. According to page 6 of Pub 501, under the heading, "marital status", if you were legally separated from your spouse under a divorce or separate maintenance decree, you are considered unmarried for the whole year. In this case you would NOT be eligible to file as married filing jointly or married filing separately. https://www.irs.gov/pub/irs-pdf/p501.pdf. Please refer to the following FAQs to learn more about filing Married Filing Jointly, Married Filing Separately, and Head of Household. https://ttlc.intuit.com/replies/3288477. https://ttlc.intuit.com/replies/4775330. From <https://ttlc.intuit.com/questions/1894553-do-i-qualify-for-head-of-household