Ontario, CA Parking Rules: Curb Color Rules (2026)

Curb-marking meanings in the unincorporated County are governed by California Vehicle Code Section 21458, which standardizes curb colors statewide so they carry the same meaning regardless of jurisdiction. Under Section 21458(a): red means 'no stopping, standing, or parking, whether the vehicle is attended or unattended,' except a bus may stop in a red zone marked as a bus loading zone; yellow means 'stopping only for the purpose of loading or unloading passengers or freight' for the time specified by local ordinance; white means stopping only for loading or unloading of passengers, or depositing mail in an adjacent mailbox; green means 'time limit parking specified by local ordinance'; and blue means parking 'limited exclusively to the vehicles of disabled persons and disabled veterans.' These markings are regulatory only when installed by, or with the authority of, the public agency with jurisdiction over the roadway-County Public Works for County-maintained roads. Private property owners and residents may not paint public curbs to create or extend parking restrictions; doing so is not enforceable and can itself be a violation. On the public street, the County also relies on County Code Title 5 traffic provisions and posted signage to set time limits and special zones that complement the curb colors. Because most unincorporated residential streets have unpainted curbs, the Vehicle Code's curb-color scheme and the 72-hour street-storage rule (County Code Section 52.0119) are the chief day-to-day controls.