Costco Gas Prices in Ontario, California
Latest reported regular prices per gallon from 1 of 2 Costco gas stations; most recent report Nov 13, 2026 (UTC). Prices may vary at the pump.
Average Price
$4.89/gal
Lowest Price
$4.89/gal
Highest Price
$4.89/gal
All Costco Gas Stations in Ontario, California
Browse every listed location and open its latest reported prices and station details.