Mark Simon Austin Tanner (born November 1970) is a British Anglican bishop and academic.

[2] Tanner was ordained in the Church of England as a deacon in 1998,[2] and as a priest on 3 July 1999 by Michael Langrish, Bishop of Birkenhead.

[4] In August 2011, Tanner became warden of Cranmer Hall, Durham, a Church of England theological college in the Open Evangelical tradition.

[8][9] The confirmation of his election as Bishop of Chester, by which he legally took office, took place on 15 July 2020: it was undertaken online due to the COVID-19 pandemic.

[10][11] On 7 June 2024, he gave the sermon at the wedding of Hugh Grosvenor, 7th Duke of Westminster and Olivia Grace Henson.

[12] He abstained during a vote on introducing "standalone services for same-sex couples" on a trial basis during a meeting of the General Synod in November 2023; the motion passed.