Llansantffraid-ym-Mechain is a large village in the community of Llansantffraid, in Powys, Mid Wales. It is close to the border with Shropshire in England, about 7 miles (11 km) south-west of Oswestry and 8 miles (13 km) north of Welshpool. It is on the A495 road and is at the confluence of the River Vyrnwy and the River Cain. The population as of the 2011 UK census was 1,415. The community includes the village of Deuddwr and several hamlets.