Legally married same-sex couples will now be allowed the same tax benefits as heterosexual couples.
On Thursday, the Internal Revenue Service and the U.S.Treasury Department outlined the new regulations.
Treasury Secretary Jacob Lew said the new rules will provide "clear, coherent tax filing guidance for all legally married same-sex couples nationwide."
The new rules will allow gay couples to file federal joint tax returns even if the state where they live does not recognize their union.
The move comes on the heels of the recent U.S. Supreme Court ruling which invalidated part of the Defense of Marriage Act, or DOMA.
Gay rights advocates praised the ruling.
"These families finally (have) access to crucial tax benefits and protections previously denied to them under the discriminatory Defense of Marriage Act," Human Rights Campaign President Chad Griffin said.
Meanwhile, Brian Brown with the National Organization of Marriage believes giving same-sex couples the right to file jointly continues the pattern of lawlessness across the country.