- Voters in Mt Albert are choosing a replacement for David Shearer who left politics for the UN.
- Labour's candidate is Jacinda Ardern, currently a list MP.
- The Green Party candidate is also a current list MP, Julie Anne Genter.
- National is not fielding a candidate.
- The other candidates are independents or representatives of small parties that don't have any MPs.
- Newshub is publishing live updates of the results as they come in.
9:05pm: "I could sit here, we could pick over the results and talk about the margins and what they told us; but for the people out there, what matters is what we can do with it and what change we can bring," says Ms Ardern of her win.
"Here in Mt Albert there is so much to celebrate, but we need to go back to the basics - affordable housing, the ability to get around our city, clean spaces for kids to grow up in, water that you can swim in, creating the best schools and the safest neighbourhoods... I vow I will advocate for all these things, but real change comes when Labour is in government."
8:45pm: 100 percent of the preliminary votes have now been counted - 12,971 in total. Ms Ardern has won comfortably with 77 percent. In second place is Ms Genter with 1489 votes, while Geoff Simmons of The Opportunities Party is in third with 600. Independent Penny Bright has come in at sixth place with 131 votes.
8:40pm: Ms Adern has 9233 of the 12024 votes counted, maintaining the 77 percent lead she took early on.
8:24pm: With 89.3 of the vote counted Ms Ardern is on 8389 votes - giving her a margin of 7,154.
8:18pm: 78.6 percent of the vote has been counted and Ms Ardern is now leading by 6,439 votes. Mr Simmons has increased his vote count to 463. Ms Genter is on 1096.
8:10pm: Ms Ardern is leading by 5,098 votes. Mr Carolan is now 16 votes ahead of Ms Bright. Labour leader Andrew Little has arrived at Ms Adern's victory party.
8:00pm: 57.1 percent of the vote has been counted, and Ms Ardern now has 5780 votes. Ms Genter has 869 votes and Mr Simmons has 321.
7:56pm: Half the vote has been counted, and Ms Ardern is ahead of Ms Genter by 5303 to 790.
7:48pm: With 28.6 percent of the vote counted, Ms Ardern has increased her margin to 3,005 votes. Joe Carolan is 10 votes ahead of Penny Bright for fifth place.
7:37pm: Newshub political editor Patrick Gower says Ms Ardern is almost certain to be elected MP.
7:31pm: A quarter of the votes have been counted. Ms Ardern is leading by 2,787 votes. Geoff Simmons of The Opportunities Party is third with 188 votes.
7:29pm: With 4150 votes counted, Ms Ardern now has 3173 votes - 76.4 percent of the vote.
7:14pm: Ms Ardern has 3117 votes compared to Ms Genter's 464, with 17.9 percent counted.
7:00pm: Jacinda Ardern is leading by a margin of 2,616 votes, with 14.3 percent of the votes counted.