Original Article Apr 6, 4:16 AM EDT Daily cost of keeping inmate in county jail now about $62 MESA, Ariz. (AP) -- The cost of keeping an inmate locked up for a day in Maricopa County jails is now about $62. On Wednesday, the county's board of supervisors approved a 10 percent increase to a fee that the jails charge cities and local police agencies to hold their misdemeanor suspects. What's driving up the cost is the construction of more jails. The county has built two new jails, both of which opened about a year ago. Together, they cost about $214 million to build. Loretta Barkell, the sheriff's chief financial officer, said money spent last year on standard things such as employee benefits, pay raises, software upgrades, radio equipment and regular inflation also helped push the cost up slightly.