Treasury Department: Legally-married same sex couples qualify to file joint taxes regardless of their state

The US government on Thursday announced that legally married gay couples will be treated the same as married couples for federal tax purposes.

The decision applies to legally married same-sex couples whether they live in a state that recognizes the marriage or not, the US Treasury Department and the Internal Revenue Service said in a statement.

"Today's ruling provides certainty and clear, coherent tax filing guidance for all legally married same-sex couples nationwide. It provides access to benefits, responsibilities and protections under federal tax law that all Americans deserve," said Treasury Secretary Jacob Lew said in the statement.

"This ruling also assures legally married same-sex couples that they can move freely throughout the country knowing that their federal filing status will not change."

Those couples will have the same treatment under federal tax law provisions where marriage is a factor, including their filing status personal and dependency exemptions that they can claim, and other tax benefits that heterosexual couples currently enjoy.

The ruling comes after the US Supreme Court, in a landmark decision on June 26, struck down the Defense of Marriage Act (DOMA), which denied federal benefits to married gay and lesbian couples by strictly defining marriage as a union between a man and a woman.

As a result the federal government was allowed to recognize same sex couples in all federal matters, such as sharing pension benefits -- the issue that brought the case to the highest court.