| Country: | Wales |
| Official Name: | Alltmawr |
| Coordinates: | 52.1122°N -3.3528°W |
| Cardiff Distance Mi: | 44 |
| Cardiff Distance Km: | 71 |
| London Distance Mi: | 144 |
| London Distance Km: | 232 |
| Unitary Wales: | Powys |
| Community Wales: | Erwood |
| Constituency Welsh Assembly: | Brecon and Radnorshire |
| Constituency Westminster: | Brecon and Radnorshire |
| Post Town: | BUILTH WELLS |
| Postcode District: | LD2 |
| Postcode Area: | LD |
| Os Grid Reference: | SO 0746 4685 |
Alltmawr is a village in the community of Erwood, Powys, Wales, which is 44 miles (71 km) from Cardiff and 144 miles (232 km) from London.[1] St Mauritius Church at Alltmawr is counted as being one of the smallest in Wales.[2]