The Ohio Department of Taxation has issued guidance for filing Ohio personal income tax returns by same-sex couples who were married elsewhere but live in Ohio. Information Release IT 2013-01 — Filing Guidance for Taxpayers Filing a Joint Federal Income Tax Return With Someone of the Same Gender — Issued October 11, 2013, was issued after the announcement by the Internal Revenue Service (IRS) that it would allow legally married same-sex couples to file jointly, even if they reside in a state that doesn’t recognize the relationship. This announcement followed the ruling of the United States Supreme Court that struck down the federal Defense of Marriage Act (DOMA) earlier this year.

The information release provides that same-sex couples will need to file separate state income tax returns. Ohio typically keeps its tax rules in line with the federal code to allow Ohioans to use federal adjusted gross income as the starting point for state returns. But in this case, the Ohio Constitution's ban on legal recognition of same-sex unions prevents that, the department said. Same-sex couples filing jointly at the federal level will have to file an Ohio Schedule IT S form, which will help them calculate how to report their federal adjusted gross income on their individual returns, with their state returns. They may not file as “married,” but rather must file as “single” or as “head of household,” as the case may be.

A copy of the information release may be found here.