"Billy the Exterminator" won't be bugged by those pesky inmates looking for some late night love ... because he just got a reprieve by a judge.
The A&E star -- real name William Bretherton -- and his wife, Mary, were busted last April when cops caught them with synthetic marijuana and a smoking device. Both parties pled guilty Friday to drug possession.
As part of the plea deal ... Billy was sentenced to 60 days in jail, BUT he won't have to serve time if he pays a $500 fine, completes four 8-hour days of community service, undergoes substance abuse evaluation and steers clear of drugs and alcohol.
To make sure he's clean ... Billy must submit to random drug testing.
If Billy stays clean for a year, he's free to pursue his dream of crucifying all the critters his little heart desires.