The degree to which residents of British inner cities and suburbs have diverged in their voting behaviour over the post-war period is analysed in this article. Examining aggregate election results by constituency, it is demonstrated that residents of inner cities and suburbs are indeed polarizing in their electoral choices. OLS regression analysis is conducted using constituency-level data to determine the relevance of intra-urban differences for understanding geographic variation in the vote in relation to those for region, size of conurbation and urban–rural distinctions. Results show that urban place of residence is particularly important for understanding the shifting geography of Conservative support. The implications of this research for electoral change in Britain are discussed.