Thanks to a 2013 Supreme Court ruling recognizing same-sex marriage on the federal level, couples who have entered into a valid same-sex marriage must file federal tax returns using either married filing jointly or married filing separately status. The ruling applies to couples married in a state that legally recognizes same-sex marriage, even if the couple lives in a state that does not recognize the marriage [source: IRS Treasury].
That ruling, as well as new IRS regulations, means that you and your same-sex spouse can now legally take advantage of all of the married tax benefits in this list. Keep in mind that this ruling has nothing to do with state taxes. You may still have to file your state tax returns individually.