Santa Clarita is a suburban city in northwestern Los Angeles County, California, United States. With a 2020 census population of 228,673, it is the third-most populous city in Los Angeles County, the 17th-most populous in California, and the 105th-most populous city in the United States. It is located about 30 miles (48 km) northwest of downtown Los Angeles, and occupies 70.75 square miles (183.2 km2) of land in the Santa Clarita Valley, along the Santa Clara River. It is a classic example of a U.S. edge city, satellite city, or boomburb.