Prior to his election as an MP, Esterson was a councillor for River Ward in Medway.[7] When Medway Council was created in 1997, Esterson was elected to represent Town Ward. He represented Town Ward until 2003, when boundary changes were implemented. He was a councillor for St Margaret's and Borstal ward on Rochester-upon-Medway City Council which was dissolved to form Medway Council.[8] During his time as a councillor, Esterson served on the Environment, Food and Rural Affairs; Education; Community and Local Government; and Treasury Select Committees.[9]
Esterson contributed to the Hillsborough debate in the House of Commons on 17 October 2011 by reading directly the words of a bereaved father. In September 2011 he contributed to the book What next for Labour? Ideas for a new generation. His chapter was entitled A Campaigning Party.[11]
In January 2015, Esterson proposed a bill which would introduce compulsory labelling of alcoholic drinks warning about potential dangers from drinking during pregnancy.[12]
At the 2015 general election, Esterson was re-elected as MP for Sefton Central with an increased vote share of 53.8% and an increased majority of 11,846.[13][14]
Esterson was again re-elected at the snap 2017 general election with an increased vote share of 63% and an increased majority of 15,618.[17] At the 2019 general election, Esterson was again re-elected, with a decreased vote share of 57.5% and a decreased majority of 15,122.[18][19]
