Early voting in the Fannie Bay by-election, forced by the resignation of former chief minister Michael Gunner, will open on August 8.
The Northern Territory Electoral Commission has released the timetable for the August 20 poll with eligible voters having until the close of business on Friday to enrol.
Postal voting applications can be made until August 18.
Candidates will have until midday on August 4 to nominate.
At the 2020 Territory election, just under 5500 people were registered to vote in Fannie Bay with Mr Gunner beating his CLP opponent Tracey Hayes by 831 votes in the final two-party count.
He first took the seat in 2008, eventually going on to become the first Territory-born Top End leader at the 2016 election.
The 46-year-old has been on the back bench since May when he resigned from the top job.
On Wednesday evening he announced he was quitting parliament in a speech to the NT Legislative Assembly.
"In May I stepped down as chief minister. Tonight I resigned as the Member for Fannie Bay. The reasons are the same: what is best for the people I serve and what is best for my family," Mr Gunner wrote on Facebook.
"This job, being a member, is one that is and should be all-consuming ... I don't know any other way than going full-on."
Mr Gunner said he had no immediate plans to return to the workforce but was not in a position to "retire for life".
"I have no plans yet and I can't see myself working again until late this year at the earliest but my priorities are clear," he said.
"My family come first, supporting my wife, raising my boys."
