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 103rd-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 …