 The arms were adopted by the unified town after the annexation of Auenstein, and were officially granted by the District of Heilbronn on January 24, 1978.Ilsfeld is twinned with Ottery St Mary (Devon, United Kingdom), Auenstein (Aargau, Switzerland) and Moşna (Sibiu County, Romania).Ilsfeld and Auenstein each have a Protestant parish; Ilsfeld also has a New Apostolic parish.