The rules would, among other things, allow some broadcast stations to make a "phased transition" to digital broadcasting.
Stations also will be allowed to reduce or terminate their analog service before the, "if doing so is necessary to achieve their transition," the FCC said Monday.
"The rules we adopt in this item attempt to provide broadcasters the flexibility they need while at the same time ensuring that any disruption to over-the-air viewers is minimized to the fullest extent possible," FCC Chairman Kevin Martin said in a statement.
Congress ordered the switch to digital television to free up public airwaves for other uses, such as for police and fire departments. The switch will also improve picture and sound for TV viewers.
U.S. lawmakers, many of whom face re-election in November, are closely watching the switch because their constituents who own analog television sets will be unable to watch programs sent via digital signals unless they subscribe to satellite or digital cable, get a converter box, or buy a new digital TV.
The government will subsidize the cost of buying a digital-analog converter box by offering $40 discount coupons to anyone who owns an analog television set.
Democratic FCC commissioner Michael Copps said that even though he supported the new rules, he was frustrated that.
Copps said he and the other commissioners were discussing the idea of conducting "one or more" digital transition tests around the United States before the nationwide deadline.
"I recognize there may be legal, technical, and practical challenges with planning and conducting such a test this close to the national transition date. But I believe it can be done. At least--for the sake of a successful DTV transition--let's hope it can," Copps said.