Nantmel is a village and a community in Radnorshire, Powys, Wales, and is 76.5 miles from Cardiff and 150.5 miles from London. In 2011 the population of Nantmel was 621 with 11.8% of them able to speak Welsh. The population of the community was 637 as of the 2011 UK Census. In 1870, John Marius Wilson described the village as a parish and village in the Rhayader district or Radnor.