Defense Secretary Chuck Hagel says the Pentagon will begin the process to extend health care, housing and other federal benefits to the same-sex spouses of military members as soon as possible.
Wednesday's Supreme Court decision opens the door for married gay couples to get federal benefits.
Defense officials estimate there are 18,000 same-sex couples in the active duty, National Guard and Reserves. It's unclear how many of those are married. The court ruling also could allow same-sex spouses to be buried at Arlington Cemetery.
The Pentagon has said that by Oct. 1, it would extend a variety of benefits to same-sex partners, including access to on-base commissaries and some health and welfare programs.
The repeal of the ban on openly gay military service took effect in September 2011.