It covers all the English county of Nottinghamshire and a few parishes in South Yorkshire.

It is bordered by the dioceses of Derby, Leicester, Lincoln and Sheffield.

Until 2005 the diocese was named simply Southwell, but in February the diocesan synod requested a change of name, which was approved by the General Synod of the Church of England in July and by the Privy Council on 15 November 2005.

On 5 February 1884 it was taken from Lincoln and united with the archdeaconry of Derby (covering, roughly, Derbyshire), which was taken from the Diocese of Lichfield.

Alternative episcopal oversight (for the few parishes in the diocese which do not receive the ministry of priests who are women) is provided by a provincial episcopal visitor (PEV), the Bishop suffragan of Beverley, Stephen Race.