 From 2008 to 2009, Filsell was Principal Organist of the Basilica of the National Shrine of the Immaculate Conception in Washington, D.C.He then directed the music at Old St Paul's Episcopal Church, Baltimore, and in 2010 became artist-in-residence at Washington National Cathedral, where he performed Olivier Messiaen's work "La Nativité du Seigneur" on 18 December 2011.In 2019 he succeeded Daniel Hyde as Director of Music at Saint Thomas' Church, Manhattan, New York City.