| Place Name | Castaic |
| Place Type | Census Designated Place |
| ZIP Code(s) | 91384 |
| GEOID | 0611796 |
| County | Los Angeles County |
| Area Code(s) | 661 |
| Timezone | Pacific Standard Time (PST) |
| Population (2021) | 18,017 |
| Population Growth Rate (2010-19) | -0.41% |
| Majority Ethnicity | White 58.44% |
| Metro/Micro Stats Area | Los Angeles-Long Beach-Anaheim, CA |
| US Congressional District(s) | California 25th |
| State Assembly Districts | 38 |
| State Senate Districts | 21 |
| Race/Ethnicy | Percentage of Population (2021) |
|---|---|
| White | 58.44% |
| African American | 1.63% |
| Hispanic | 1.16% |
| Asian | 11.61% |
| Native American | 0.09% |
| Hawaiin/Pacific Islander | 27.06% |