BBC7 was launched as a digital-only radio station on 15th December 2002 (its opening hours broadcast simultaneously on BBC Radio 4), with the aim to provide an outlet for the BBC's archive comedy and drama, as well as modern programmes made specifically for the channel (e.g. themed Childrens programmes in the early days). The channel received the Sony Radio Academy Award for station sound in 2003, and received a silver for Short-Form in 2005.

In October 2008 the channel was renamed BBC Radio 7 in line with the BBC's other radio stations, and in 2011 it was rebranded as BBC Radio 4 Extra, and as well as its existing archive programming (Dad's Army, The Navy Lark, Hancock's Half Hour, Radio Active to name just a few), also now broadcast similar and archive shows to its 'parent' channel BBC Radio 4 (e.g. Desert Island Discs, Dead Ringers).

Doctor Who featured on the channel a number of times, in its dedicated 7th Dimension science-fiction segment (usually 6:00pm-7:00pm). The existing three Radio 4 adventures (the Jon Pertwee stories The Paradise Of Death and The Ghosts On NSpace and the Colin Baker story Slipback) featured in its early years, whilst in later years BBC Audio Target novelisation were broadcast, and also Eighth Doctor stories produced by Big Finish. In 2013 the channel broadcast a three hour programme about Doctor Who, and in 2016 kicked off a run of Big Finish adventures featuring Colin Baker.