Larimer County Chief Judge Stephen Schapanski accepted the agreement that prosecutors reached with Richard and Mayumi Heene, who weren't at Tuesday's hearing.
The Larimer County sheriff's office and other agencies had sought $48,000 for responding to the Oct. 15 incident. The Heenes reported their 6-year-old son had floated away in a homemade UFO-shaped helium balloon, touching off a scramble of dozens of emergency responders and two Colorado National Guard helicopters.
The boy wasn't on the balloon and was later found at his home in Fort Collins, about 60 miles north of Denver. Authorities accused the Heenes of staging a hoax to get publicity for reality TV shows they were trying to pitch.
The Heenes' attorneys had argued the couple should pay only a small amount in compensation. Richard Heene's attorney, David Lane, said in January that it appeared authorities wanted to make money on the episode.
The Heenes' attorneys didn't immediately return calls after business hours Tuesday.
Prosecutors reduced the amount sought, agreeing to drop the sheriff's request for investigative costs. Damage to a farmer's wheat crop where the balloon landed hasn't been calculated.
Richard Heene was sentenced to 90 days in jail for falsely influencing authorities. Mayumi Heene was sentenced to 20 days for filing a false report.