The agency landed the brief for the body, which handles communications surrounding the digital switchover of the TV signal, after a pitch against Manning Gottlieb OMD, Starcom MediaVest Group, MPG Media Contacts and Initiative that was overseen by Oystercatchers.
Digital UK, which is expected to spend up to £26 million on media up to August 2012, reappointed MediaCom on a two-year contract after five years with the agency.
MediaCom will work alongside the creative agency DLKW Lowe and the direct agency Elvis on the business.
In January, Digital UK moved its advertising account from Abbott Mead Vickers BBDO into DLKW after a pitch. Elvis was hired to handle its direct marketing in February 2009, scooping it from the incumbent, Rapier.
Digital UK was established in 2005 and its shareholders include the major terrestrial broadcasters and the transmission companies SDN and Arqiva.