The San Ardo Oil Field is a large oil field in Monterey County, California, in the United States. It is in the upper Salinas Valley, about five miles (8 km) south of the small town of San Ardo, and about twenty miles (32 km) north of Paso Robles. With an estimated ultimate recovery of 530,000,000 barrels (84,000,000 m³) of oil, it is the 13th-largest oil field in California, and of the top twenty California oil fields in size, it is the most recent to be discovered (1947). As of the end of 2006, the principal operators of the field were Chevron Corp.