Why early election results can mislead: lessons from 2017, 2020 and 2023
Seat totals have changed after election night at each of the last three New Zealand elections. Here's what moved, why it happens, and how to avoid being fooled on 7 November.
In this guide
At 8pm on election night it can look as if the result is settled. Sometimes it is. But at each of the last three New Zealand elections, seat totals changed between the election night count and the official result, and in each case it mattered.
Here's what happened, why it happens, and what to watch on 7 November 2026.
Quick answer
- Early results are mostly advance votes and small voting places, which aren't a random sample.
- The election night count leaves out special votes: 603,257 in 2023, about 700,000 expected in 2026.
- Seats moved after election night in 2017, 2020 and 2023, by one or two seats per party.
- The safest approach: wait until half the voting places are in, and treat close seats as open until 27 November.
What changed at the last three elections
Seats on election night vs the official result
2023
- National 50 → 48
- Green 14 → 15
- Te Pāti Māori 4 → 6
2020
- Labour 64 → 65
- National 35 → 33
- Māori Party 1 → 2
2017
- National 58 → 56
- Labour 45 → 46
- Green 7 → 8
2023: National 50 to 48
On election night National had 50 seats, and with ACT's 11 it had 61 of 121, a bare majority. Once special votes were counted, National dropped to 48, the Greens rose from 14 to 15 and Te Pāti Māori from 4 to 6. Te Pāti Māori's extra electorate wins created a two-seat overhang, so Parliament had 122 seats and the majority line moved to 62. National and ACT together had 59, so NZ First's eight seats became necessary for a government.
2020: Labour 64 to 65
Labour won an outright majority on election night with 64 seats. The specials added one more, to 65, while National fell from 35 to 33 and the Māori Party picked up a second seat. The overall result didn't change, but it showed the same pattern of specials helping some parties more than others.
2017: National 58 to 56
On election night National had 58 seats and the combined Labour and Green total was 52. After specials, National dropped to 56, Labour rose to 46 and the Greens to 8. That narrowed the gap, and NZ First, with nine seats, chose to form a government with Labour, supported by the Greens.
Why early results lean one way
Three things make the first numbers unrepresentative.
- Advance votes come first. Advance votes are counted on election day in secure rooms so they can be released soon after 7pm. People who vote early differ, on average, from people who vote on the day.
- Small places report first. Rural voting places have fewer votes to count and finish earlier. Big urban places finish later.
- Special votes come last. They're cast by people who enrolled late, voted outside their electorate, voted from overseas or are on the unpublished roll. These voters skew younger and more mobile, and they've tended to split differently from ordinary voters.
Special votes keep growing
- 2017446,287
- 2020504,621
- 2023603,257
- 2026~700,000
The maths of a small shift
A one- or two-point shift sounds small, but under MMP it can move seats.
- Each seat is worth roughly 0.8% of the party vote in a 120-seat Parliament.
- Parties near the edge of a seat under the Sainte-Laguë formula can gain or lose one with a tiny change. See our worked example.
- A party near the 5% threshold can go from five or six seats to none.
- An electorate won by a few hundred votes can flip, and if it brings in a small party, that changes everything.
How to avoid being fooled on the night
- Check the percentage counted. Under 50% of voting places, assume things will move.
- Watch the gap against what's left. A lead smaller than the remaining vote isn't safe.
- Mentally adjust for specials. If the past pattern holds, parties that have done well with specials may gain a seat.
- Treat 61 as a moving target. If there's an overhang, the majority line goes up.
- Listen to the cautious analysts. The best ones say "projected" or "provisional" for a reason.
What could be different in 2026
Some things could change the usual pattern this time:
- More special votes. About 700,000 are expected, partly because the Electoral Amendment Act 2025 ended election day enrolment. Late enrollers vote specially.
- New boundaries. Several electorates were redrawn, which could mean more people voting outside their electorate. See the boundary changes.
- Record early voting. The advance vote is bigger again, so the first results will be bigger and more of the vote will be known early.
Questions and answers
Why do election results change after election night?
Because the election night count doesn't include special votes, which were a fifth of all votes in 2023. When they're counted, seat totals can shift by a seat or two.
How much did the 2023 result change?
National went from 50 seats on election night to 48. The Greens went from 14 to 15 and Te Pāti Māori from 4 to 6, creating a 122-seat Parliament.
Do special votes always favour the left?
Not always, and not by design. At recent elections they've helped Labour, the Greens and Te Pāti Māori more than National, but the pattern depends on who casts them, which can change.
When is it safe to call the result?
When the remaining votes, including specials, can't change the outcome. For a clear result that might be 10pm on election night. For a close one, it could be 27 November.
Sources
- 2023 New Zealand general election: preliminary and official results.
- Electoral Commission: 2017, 2020 and 2023 official results and 2026 special vote estimate.
- 2023 preliminary results release.
This guide is general information about New Zealand elections, checked against the sources linked above on 3 November 2026. For anything about your own enrolment or vote, check vote.nz or call the Electoral Commission on 0800 36 76 56.
Keep reading
Special votes explained: why the result can change after election night
About 700,000 special votes are expected in 2026. Here's who casts them, why they're counted later, how they've changed seat numbers before and when the official result lands.
Advance vote results: why they're counted first and what they tell you
Advance votes are the first results released on election night. Here's how they're counted, how big they are in 2026, and why they can lean differently from the final result.
How to read election night results like a pro
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