Who will be New Zealand's prime minister after the 2026 election?

Both leaders have boxed themselves in with public promises. Winston Peters says NZ First won't do a deal with Labour, and in August Chris Hipkins answered by ruling out NZ First himself, citing what he called overt racism. Luxon, for his part, has ruled out working with the Opportunity Party. Those are costly signals because breaking them after the election would carry a large audience cost, and together they fix the two blocs in place.

Voters are unhappy with both major parties. Labour and National are each below 30 percent, 56 percent say the country is heading in the wrong direction, and Hipkins leads Luxon as preferred prime minister 45 to 35 in the latest Post poll. That is a warning sign for Luxon personally, but preferred prime minister ratings do not decide New Zealand elections: the party vote and the coalition arithmetic do. Peters's record of choosing between blocs after the vote is the one behavior Luxon's allies openly worry about.

Reference class: New Zealand governments seeking a second term. Since 1935, only two governments have lasted a single term, both Labour, in 1957 to 1960 and 1972 to 1975. Counting the first-term governments since 1935 whose re-election bids have been decided, 9 of 11 won a second term, a base rate of about 0.82. No National-led government has ever lost after one term.

The closest analogue is 2023 in reverse: a first-term government with a weak major party, a strong NZ First and a fragmented left. It breaks because this time the minor parties are unusually large. National has lost about 11 points since 2023, much of it to ACT and NZ First, and the Opportunity Party is polling above the 5 percent threshold, which could hand the balance of power to a party Luxon has ruled out.

Start with the 0.82 historical base rate for a second term. The polls deserve far more weight 6 weeks out. The Herald-Motu poll of polls gives the National, NZ First and ACT coalition a 47.3 percent chance of forming the next government, and a four-party opposition including the Opportunity Party 41.9 percent, leaving about 11 percent for a hung parliament or other outcome. Because Labour has ruled out NZ First, most of that residual favours the right bloc, which puts the coalition's total near 0.53.

Luxon is not guaranteed the premiership even if his coalition wins; with National near 27 to 30 percent and his personal ratings trailing, we put the chance that National replaces him before or during coalition talks at about 8 percent. Blending 90 percent polls and 10 percent base rate for the coalition gives 0.9 times 0.53 plus 0.1 times 0.82, about 0.56. Multiplying by 0.92 for the leader risk gives about 0.51, which we trim to 0.50 because the polls have been volatile. Hipkins takes about 0.42, since he leads Labour in every left-bloc scenario. Kalshi last traded Luxon at 0.57.