His resignation will mean a by-election is required to fill the vacated post.
Deputy Mayor Peter Wethey will assume all mayoral responsibilities after Mr Gent's departure until the by-election.
Dale Ofsoske from Election Services, who manages Kaipara District Council's (KDC) elections, said the Local Electoral Act stipulates a by-election following a resignation between September 28 and November 20 cannot take place until February 17 the next year.
The time gap is so the required processes, notifications and postal ballots are not overlooked or put aside during Christmas break and holiday period.
In 2012, the Government put a panel of commissioners in place to run the Kaipara district, with Mr Gent the first mayor elected after Kaipara was deemed fit to look after itself.
The commission was installed to help Kaipara resolve an $80 million debt arising from the controversial Mangawhai wastewater scheme, and other serious governance issues.
The council has had four chief executives in the last five years.
The current acting chief executive, Peter Tynan, was appointed a month ago, after being recommended for the job by Mr Gent.
A qualified accountant with no local government experience, Mr Tynan had been chief executive of Southern Cross Health Society, on whose board Mr Gent is the chairman.
Mr Gent was also chairman of Kaipara's Remuneration Committee which recommended Mr Tynan to the full council.
The appointment followed the sudden resignation only weeks earlier of Graham Sibery, who was just over an year into the job.
Mr Sibery was appointed by the KDC commissioners John Robertson, Richard Booth and Peter Winder ahead of the 2016 elections. The council has refused to explain why he resigned.
Mr Sibery had replaced acting chief executive Dr Jill McPherson who was appointed after professional accountant Steve Ruru resigned in October 2014 to take up the position of chief executive of the Southland District Council.
