A group of now ex-local government politicians had to vacate their seats after being elected in the 2017 election - and by-elections aren't cheap.
There was an unusual excitement to the swearing in ceremony, and Corin Dann gets a red birthday cake.
The coalition announcement was made today in Wellington, with confirmed ministerial positions coming later this week.
Public transport will also be a priority, as will moving New Zealand towards "100% renewable energy generation", he said.
Even 1NEWS' political team had no idea when, how, and if the NZ First leader would reveal his coalition partners yesterday.
The PM-elect also implied she would be involved in arts and culture, and intelligence portfolios.
That will include at least four Cabinet positions for NZ First with the Green Party's James Shaw also in line.
"We all know the rules, we play by them," Mr English said of his party's 56 seats in opposition.
Relive an action packed day, as Jacinda Ardern became New Zealand's new Prime Minister elect.
Winston Peters ends National's nine year reign as Government in sensational fashion.
Despite losing the top job, Mr English was happy to offer his replacement some advice.
The NZ First leader has no doubt Jacinda Adern has enough experience to be PM.