San Bernardino led the six-day search for the former LAPD officer and Navy reservist.
The manhunt included 125 sheriff's deputies plus law enforcement from 10 other agencies.
The LAPD has yet to total all its costs.
Dorner was wanted for killing Cal State Fullerton assistant basketball coach Monica Quan and her fiancé Keith Lawrence. He is also suspected of killing Riverside Police Officer Michael Crain and San Bernardino Detective Jeremiah MacKay.
Dorner was eventually tracked down at an Angelus Oaks cabin, where he fired at officers during a dramatic last stand. MacKay was killed during the shootout, after which the cabin went up in flames.
Charred remains found inside the cabin were positively identified as Dorner.
An autopsy revealed Dorner died from a single gunshot wound to his head, which appeared to be self-inflicted.