Opinion polls in New Zealand elections

In New Zealand, where the general elections are scheduled for November 7, 2026, opinion polls are proliferating. However, each poll is only a blurred snapshot of public opinion at a past moment: it does not allow for predicting the election result.

Polls are estimates, not predictions

Each poll is only an estimate: a one or two point difference between two surveys is statistical noise, not a signal. Unexpected voter turnout can skew polls, as in 2020 in New Zealand, when they underestimated the Labour Party and overestimated the National Party.

Limitations of polling accuracy

Polls can also influence voting, to the detriment of smaller parties threatened by the 5% vote threshold. At nine months before the election (this article was published in English on February 3, 2026, translator's note), what can opinion polls tell us about the outcome? Not much, in truth.

Statistical uncertainties in polling

On the basis of polls alone, no one could have predicted, early in the year, the outcome of the last three elections. Trends evolved in the following months, and events - foremost among them the Covid pandemic in 2020 - reshaped the political landscape.

Polls as snapshots of public opinion

Each poll is a snapshot of public opinion at a past moment - and this snapshot is blurry, due to sampling error, statistically inevitable. A sample of 1,000 people never exactly matches the entire electorate, and the proportion of undecided voters is often not communicated.

Ethical guidelines for political polling

Polling organizations have every interest in producing results as accurate as possible, but statistical uncertainties are unavoidable. Each poll is only an estimate. And a slight difference of one or two points between two polls is "noise," not "signal."

Ethical standards for political polls

The code of ethics for political polling of the Research Association New Zealand (RANZ), the professional organization of the survey and research professions, requires that any projection of the number of seats for each party "specify that polls do not predict - they measure a moment in time."

Recent poll trends and political implications

Recent polls indicate that if elections had taken place recently, the National Party, the center-right formation of Prime Minister Christopher Luxon, would have received fewer list votes - those that determine the distribution of seats - than in the 2023 elections. The Labour Party (center-left), in opposition, might have performed better than them, but would have been disadvantaged by its potential coalition partners, the Greens (left-wing ecologists) and Te Pāti Māori (the party defending the rights of Maoris).

Voter turnout and polling accuracy

It is difficult to say whether this hypothetical election could have led to a change in government. Polls conducted in the weeks immediately preceding an election are generally close to the results. But voter turnout can completely disrupt this.

The role of political observers

A representative sample of the electorate does not necessarily correspond, demographically, to the population that actually goes to the polls. For example, in 2020, an unexpectedly high turnout led polls conducted in the month before the election to underestimate the Labour Party and overestimate the National Party.

Trends in polling results

Political observers can nevertheless use polls as indicators of the direction taken. At the time of writing, only New Zealand First (NZ First), the populist and nationalist party of Winston Peters, a member of the right-wing governing coalition, would have reason to be pleased with its average results in recent polls.

Impact on smaller parties

NZ First obtained scores of 9% or more, an increase compared to its result in the last elections (6.1%). However, the slow rise of the Labour Party during the year 2025 seems to have come at the expense of the two smallest left-wing parties.

Self-fulfilling effects of polls

Opinion polls can have self-fulfilling or "bandwagon" effects on electoral behavior. However, no cause-and-effect theory allows predicting whether this will happen, or to what extent. These effects can work in opposite directions according to individuals.

Voting behavior and polling influence

If polls show one candidate clearly in the lead, this can encourage me to vote for them (to get on the moving train). Or I can vote for another candidate (to support the outsider). Or not vote at all (since the game is already decided).

Election system and party thresholds

In a mixed proportional representation election system (MMP, for "Mixed Member Proportional") like that of New Zealand, where each voter votes both for a local representative and for a national list, only the parties that obtain 5% of the list vote or win at least one electorate enter Parliament.

Consequences of low poll results

A party credited with less than 5% in the polls, and which has little chance of winning an electorate, can find itself trapped in a self-fulfilling prophecy. Not wanting to "waste" their vote by giving it to this party, voters may choose another - which further complicates the task of this party.

Strategic voting and political alliances

Voters also ask: who will govern with whom? They may think that voting for one party is in fact helping another party to enter government - which may seem desirable or not to them.

Regulation of election polls

Because polls risk guiding public opinion rather than following it, New Zealand prohibits their publication on the day of the election, but not during the two weeks of early voting. In France, the law prohibits the publication and commentary of any electoral poll the day before and on the day of the election (translator's note).

Preventing manipulation of polls

However, these periods of prohibition are common in Europe and Latin America, and can last up to two weeks, as in Italy. There is also a risk that an unscrupulous actor will publish a fake poll result to influence voters' choices or dissuade them from voting.

Ethical considerations in polling

This is one of the reasons why the profession has adopted a code of conduct (which it itself ensures is followed). In a free society, however, the state should not prohibit institutes from conducting polls, nor should it prohibit the media from publishing their results.

Role of polls in democracy

Polls can inform voters and play a useful role in the democratic process. They also offer parties, between elections, feedback on their actions (or on how they are perceived). But they can undermine the debate when the media present them in a sensationalist or partial manner.

Critical engagement with polls

To read also: Why the multiplication of polls harms the information of voters: the lessons from the Australian case. We should let voters form their own opinion about the candidate or party that best represents them, rather than leading them to see the election as a competition told in terms of "who is rising, who is falling."

Reading polls with a critical eye

In the end, we should read the polls - and the media - with a critical eye, without taking anything for granted. It is always useful to check, for example, who conducted the survey, who commissioned it, and according to what method. Especially, do not forget that opinion polls only indicate past trends; they do not predict future results.