The Federal Communications Commission has voted to overhaul reimbursement for routing toll-free numbers, its latest move cracking down on fraud in the phone network compensation system.

An Oct. 7 order released Friday transitions most phone network charges for toll-free calls to a “bill-and-keep system,” in which carriers are paid by subscribers for routing the calls, not other carriers.

The order is aimed at stopping bad actors who have taken advantage of the legacy compensation system by flooding phone networks with robocalls to receive inflated payments from phone companies.

“The gravy train is over,” FCC Chairman Ajit Pai said in a...