[3] In 1986, Tremlett began training for ordination at Wycliffe Hall, Oxford, an Anglican theological college in the evangelical tradition.
[3] He studied patristics, and his thesis was titled "Metaphors of Salvation in the Soteriology of Origen of Alexandria".
[2] In 2003, he completed a Postgraduate Certificate in Church School Education (PGCE) at the University of Liverpool.
From 1995 to 1998, he was team vicar of the Parish of Holy Trinity with St Columba, Fareham, in the Diocese of Portsmouth.
During this time he also worked with the Doctrine Commission of the Church of England as a parliamentary research assistant and secretary.
[5] He then moved to the Diocese of Chichester, where he was vicar of St Mary's Church, Goring-by-Sea, Worthing, from 2003 to 2008.
[16] On 30 March 2022, it was announced that Tremlett is to become the next Dean of St Paul's following the retirement of David Ison, which was scheduled for September 2022.
[21] Tremlett had a cat called Badger which became well known among the students of Durham University and residents living in the city.
Announcing the news of Badger's death, Tremlett said: "Very sadly, after a short illness, he has found his place in the sun.