Under section 17 of the Constitution Act 1986, parliament expires three years "from the day fixed for the return of the writs issued for the last preceding general election of members of the House of Representatives, and no longer."

[77] As of 3 October 2023[update], the following third-party promoters were registered for the general election:[86] In early September 2023, the New Zealand Council of Trade Unions (NZCTU) launched an advertisement campaign attacking National Party leader Christopher Luxon.

The NZCTU's president Richard Wagstaff defended the union's advertisement campaign, claiming that it was targeting National's policies including the elimination of fair pay agreements, the restoration of 90-day work trials, and public sector cuts.

He also accused the National Party and its alleged surrogates including the New Zealand Taxpayers' Union, Groundswell NZ, and Hobson's Pledge of publishing attack advertisements against him and the Labour Government.

[87] In late September 2023, Hobson's Pledge launched a series of attack advertisements targeting Labour leader Chris Hipkins, with the caption "Delivers division, not outcomes.

[102] Labour's proposed GST policy attracted criticism including economist Brad Olsen, Child Poverty Action Group economist Susan St John, Health Coalition Aotearoa food expert Sally Mackay, Stuff political editor Luke Malpass, Newshub political editor Jenna Lynch, Newsroom journalist Marc Daalder, and The New Zealand Herald business journalist Jenée Tibshraeny.

[112] In response to National's campaign pledge to build a third medical school at the University of Waikato, Hipkins announced on 13 September that the Government would invest in training 335 extra doctors by 2027.

[122] On 30 September, Labour released its Rainbow Manifesto, with key policies including reformed surrogacy laws, a new LGBTQ+ refugee quota, and restrictions on gay men donating blood.

[123] On 1 October, Deputy Prime Minister Carmel Sepuloni released the party's full election manifesto, focusing on improving children's education and funding youth training and work programmes.

In 2019, list MP Jo Hayes expressed a desire to contest Te Tai Hauāuru;[127] Leader Judith Collins stated her support in July 2020, but said it would not be possible for the 2020 election due to time constraints.

[129][130] After Christopher Luxon replaced Collins as leader, he confirmed that these plans would continue,[131] but stated that it was a "pragmatic" move and that he felt Māori electorates were incompatible with the principle of "one person, one vote".

[157] On 6 September, National campaigned on investing NZ$257 million over the next four years to increase the number of electric vehicle chargers to 10,000 and stated it would end the Government's "clean car" discount programme and "ute tax.

Key provisions include establishing a new climate change ministry, expanding the criteria for carbon emissions, decriminalising drugs, boosting the refugee intake to 5,000, introducing rent controls, and building 35,000 new public homes.

[187] Contrary to the Greens, ACT leader David Seymour has said that he believes it's inequitable for a small portion of New Zealand's population to bear a substantial share of the country's tax revenue.

[192] On 16 July, ACT released their finalised list of 55 candidates, with notable newcomers including former Federated Farmers president Andrew Hoggard and former National MP Parmjeet Parmar.

[214] On 30 September, ACT unveiled its small business policy plan which involved abolishing Fair Pay Agreements, not raising the minimum wage for three years, and removing the 2 January public holiday.

[216] On 15 June, Te Pāti Māori co-leader Rāwiri Waititi released a Facebook video targeted towards Chris Hipkins and Christopher Luxon, calling for the pair to "shut their mouths and stop using our iwi as a political football to score points", in regards to the tangihanga of Steven Taiatini, who was the Ōpōtiki president of the Mongrel Mob Barbarians.

[252] According to TVNZ's and Vox Pop Lab's Vote Compass online tool, the top five issues in the general electorates were cost of living (28%), the economy (17%), healthcare (14%), crime (9%), and the environment (8%).

The Greens also support entrenching the Māori electorates, implementing the United Nations Declaration on the Rights of Indigenous Peoples and its local He Puapua strategy, and creating a citizen's assembly based on Treaty principles.

[277] A third ACT candidate Anto Coates also resigned after describing COVID-19 as a mass hysteria and writing a parody song suggesting that former Prime Minister Jacinda Ardern had thought about sending people to gulags.

Seymour defended ACT's candidate vetting process while Prime Minister Chris Hipkins and Te Pāti Māori co-leader Debbie Ngarewa-Packer accused the party of courting conspiracy theorists and being secretive respectively.

Luxon responded by agreeing that the quote was racist, but said that he was "going to make the call [to Winston Peters on election night] if it means stopping you, Te Pati Māori and the Greens from coming to power.

Te Pāti Māori president John Tamihere contested the Police statement and confirmed it would be filing a civil lawsuit against the elderly National Party campaigner following the 2023 election.

Popular election-related TikTok content included interviews featuring ACT leader David Seymour and NZ First candidate Shane Jones' rendition of the song "Don't Stop Believing."

[308] On 20 October, The Spinoff reported that several political parties had spent large sums on online advertisements on Meta Platforms' Ad Library (which appears on Facebook and Instagram) and Google.

Te Pāti Māori NZ First Opportunities Vision NZ Legalise Cannabis Outdoors Independent The following list candidates were elected: Nicola Willis (2) Paul Goldsmith (5) Melissa Lee (13) Gerry Brownlee (14) Andrew Bayly (15) Kelvin Davis (2) Grant Robertson (4) Jan Tinetti (6) Ayesha Verrall (7) Willie Jackson (8) Willow-Jean Prime (9) Damien O'Connor (10) Adrian Rurawhe (11) Andrew Little (12) David Parker (13) Peeni Henare (14) Priyanca Radhakrishnan (15) Kieran McAnulty (16) Ginny Andersen (17) Jo Luxton (19) Rino Tirikatene (21) Deborah Russell (22) Marama Davidson (1) James Shaw (2) Teanau Tuiono (5) Lan Pham (6) Golriz Ghahraman (7) Ricardo Menéndez March (8) Steve Abel (9) Hūhana Lyndon (10) Efeso Collins (11) Scott Willis (12) Darleen Tana (13) Kahurangi Carter (14) Nicole McKee (3) Todd Stephenson (4) Andrew Hoggard (5) Karen Chhour (6) Mark Cameron (7) Simon Court (8) Parmjeet Parmar (9) Laura Trask (10) Cameron Luxton (11) Winston Peters (1) Shane Jones (2) Casey Costello (3) Mark Patterson (4) Jenny Marcroft (5) Jamie Arbuckle (6) Andy Foster (7) Tanya Unkovich (8) Andrew Little was elected as a Labour Party list MP but resigned, effective from 5 December, after Labour lost the election.

[362] Following the release of final results on 3 November, Nicholas lost her Te Atatū electorate to Labour's Phil Twyford by a margin of 131 votes whilst Loheni was ranked too low on the list, (25), to get into parliament.

[375] On 5 June, Vance reported that the Labour Party had filed a complaint against Te Pāti Māori in November 2023 for allegedly using personal information collected during the COVID-19 immunisation programme for political campaigning purposes during the 2023 election, which is illegal under New Zealand electoral law.

[383] On 11 February 2025, The New Zealand Herald reported that Detective Superintendent Ross McKay was leading an inquiry into allegations regarding Te Pāti Māori's misuse of census data and Covid-19 vaccination information at Manurewa Marae for electoral campaigning purposes.

He noted that out of the 1.06 million eligible voters who did not vote, most statistically were renters from the youngest demographics, and claimed that National had efficiently mobilised support for landlords in a way Labour had failed to do for tenants.