Template:2020 NZ election forecasts
The use of mixed-member proportional representation allows ready conversion of a party's support into a party vote percentage and therefore a number of seats in Parliament. Projections generally assume no changes to electorate seats each party holds (ACT retains Epsom, Labour retains Waiariki, etc.) unless there is a specific reason to assume change. For example, after Peter Dunne announced his retirement, projections stopped assuming United Future would retain Ōhāriu. Other parties that do not pass the 5% threshold are assumed to not to win an electorate and therefore gain no seats.
Radio New Zealand takes a "poll of polls" average to produce their forecast. The New Zealand Herald bases theirs on a predictive model incorporating poll data as well as past election results and past poll accuracy.[1] Newshub and 1 News and produce projections based on their own polls only.
When determining the scenarios for the overall result, the minimum parties necessary to form majority governments are listed (provided parties have indicated openness to working together). Actual governments formed may include other parties beyond the minimum required for a majority. This happened after the 2014 election, when National only needed one seat from another party to reach a 61-seat majority, but they formed a 64-seat government with Māori, ACT and United Future.
| Party | 2017 election result | Roy Morgan[2] 30 Oct – 12 Nov 2017 poll |
1 News Colmar Brunton[3] 28 July-1 Aug 2018 poll |
Radio NZ[4] 5 Jun 2018 poll of polls |
Newshub Reid Research[5] 17–24 May 2018 poll | |
|---|---|---|---|---|---|---|
| National | 56 | 51 | 55 | 57 | 58 | |
| Labour | 46 | 49 | 51 | 54 | 55 | |
| NZ First | 9 | 6 | 6 | 0 | 0 | |
| Green | 8 | 13 | 7 | 8 | 8 | |
| ACT | 1 | 1 | 1 | 1 | 1* | |
| Seats in Parliament | 120 | 120 | 120 | 120 | 122 | |
| Overall result (majority) | National−NZ First (65) | Labour−Green (62) | Labour−Green-NZ First (64) | Labour−Green (62) | Labour–Green (63) | |
| Labour−Green−NZ First (63) | ||||||
| Note: Forecasted seats are currently calculated using the Electoral Commission's MMP seat allocation calculator, based on polling results. | ||||||
- * indicates an overhang seat
- ^ "Herald election forecasts explained". NZ Herald.
- ^ http://www.roymorgan.com/findings/7419-roy-morgan-new-zealand-voting-intention-november-2017-201711220740
- ^ https://www.tvnz.co.nz/one-news/new-zealand/simon-bridges-still-struggling-cut-through-voters-latest-1-news-colmar-brunton-poll-shows 1 News Colmar Brunton
- ^ https://www.radionz.co.nz/news/political/358890/no-budget-lift-for-labour-in-polls-but-support-for-pm-still-strong
- ^ http://www.newshub.co.nz/home/politics/2018/05/simon-bridges-failing-to-connect-with-voters-newshub-poll.html