| Place Name | El Castillo |
| Place Type | Census Designated Place |
| ZIP Code(s) | 78582 |
| County | Starr County |
| Area Code(s) | 956 |
| Timezone | Central Standard Time (CST) |
| Population (2022) | 76 |
| Population Growth Rate (2010-19) | 16.49% |
| Majority Ethnicity | White 69.13% |
| Metro/Micro Stats Area | Rio Grande City-Roma, TX |
| US Congressional District(s) | Texas 28th |
| State House Districts | 31 |
| State Senate Districts | 21 |
| Race/Ethnicy | Percentage of Population (2021) |
|---|---|
| White | 69.13% |
| African American | 0% |
| Hispanic | 0% |
| Asian | 0% |
| Native American | 0% |
| Hawaiin/Pacific Islander | 30.87% |