| Thornhill | |
| Pushpin Map: | South Africa Eastern Cape#South Africa |
| Coordinates: | -33.895°N 25.141°W |
| Subdivision Type: | Country |
| Subdivision Name: | South Africa |
| Subdivision Type1: | Province |
| Subdivision Name1: | Eastern Cape |
| Subdivision Type2: | District |
| Subdivision Name2: | Sarah Baartman |
| Subdivision Type3: | Municipality |
| Subdivision Name3: | Kouga |
| Subdivision Type4: | Main Place |
| Established Title: | Established |
| Leader Title: | Councillor |
| Area Footnotes: | [1] |
| Area Total Km2: | 1.26 |
| Population Total: | 2462 |
| Population As Of: | 2011 |
| Population Density Km2: | auto |
| Demographics Type1: | Racial makeup (2011) |
| Demographics1 Title1: | Black African |
| Demographics1 Info1: | 44.4% |
| Demographics1 Title2: | Coloured |
| Demographics1 Info2: | 53.0% |
| Demographics1 Title3: | Indian/Asian |
| Demographics1 Info3: | 0.1% |
| Demographics1 Title4: | White |
| Demographics1 Info4: | 1.8% |
| Demographics1 Title5: | Other |
| Demographics1 Info5: | 0.7% |
| Demographics Type2: | First languages (2011) |
| Demographics2 Title1: | Afrikaans |
| Demographics2 Info1: | 58.1% |
| Demographics2 Title2: | Xhosa |
| Demographics2 Info2: | 37.1% |
| Demographics2 Title3: | English |
| Demographics2 Info3: | 1.8% |
| Demographics2 Title5: | Other |
| Demographics2 Info5: | 3.0% |
| Timezone1: | SAST |
| Utc Offset1: | +2 |
| Postal Code Type: | Postal code (street) |
| Postal Code: | 6375 |
| Postal2 Code Type: | PO box |
| Postal2 Code: | 6375 |
| Area Code Type: | Area code |
| Area Code: | 042 |
Thornhill is a town in Kouga Local Municipality under the Sarah Baartman District Municipality in the Eastern Cape province of South Africa.