Llanfyllin is a market town and community located in Powys, Wales. Historically, the area was part of Montgomeryshire. The name Llanfyllin translates to the church or parish (llan) of St Myllin.
As of 2021, the community has a population of 1,586 residents. It encompasses several settlements, including Bodfach, Ty Crwyn, and Abernaint, along with various surrounding farms.