This article focuses on how register considerations informed and guided the design of the spoken component of the British National Corpus 2014 (Spoken BNC2014). It discusses why the compilers of the corpus sought to gather recordings from just one broad spoken register – ‘informal conversation’ – and how this and other design decisions afforded contributors to the corpus much freedom with regards to the selection of situational context for the recordings. This freedom resulted in a high level of diversity in the corpus for situational parameters such as recording location and activity type, each of which was captured in the corpus metadata. Focusing on these parameters, this article provides evidence for functional variation among the texts in the corpus and suggests that differences such as those observed presently could be analysable within the existing frameworks for analysis of register variation in spoken and written language, such as multidimensional analysis.