[2] In December 2015, Lester announced he was running to be Mayor of Wellington on a Labour Party ticket with Paul Eagle in the October 2016 local government elections.

He ran on a platform of completing Wellington projects such as the film museum, airport runway extension and a convention centre.

[13] He was elected over former Porirua Mayor Nick Leggett and fellow city councillors Jo Coughlan and Andy Foster.

[17] When Eagle resigned to become a member of Parliament in 2017, Lester appointed first-term councillor Jill Day as the new deputy mayor.

[26] He has criticised the Wellington Chamber of Commerce for signalling that it will take legal action against the Council for extending the living wage to security guards.

[27] At his mayoral campaign launch in April 2016, he announced further policies and said he would: give first-home builders a $5000 rates rebate, introduce free entry for children under five at council pools, remove the fees businesses pay to have outdoor dining on public land, and address the council's "ingrained sexism" by employing more women in senior roles.

[28] As mayor, Lester announced in February 2017 he was looking to trim council spending by $8 million to help pay for his various election promises which included strengthening the city's town hall, developing a new movie museum and convention centre, establishing an emergency reservoir at Prince of Wales park, ensuring a living wage for council employees and directing money to new infrastructure projects to help ease congestion around Wellington's Basin Reserve.

[33] After losing the mayoralty Lester took up positions as government director at Dot Loves Data[34] and savings ambassador for Simplicity, a KiwiSaver planning organisation.