Councils that brought in Māori wards without polling residents will need to hold one - or scrap the wards they had set up, the government says.
Local Government Minister Simeon Brown has announced the move, saying it reverses the previous government's "divisive changes that denied local communities the ability to determine" if Māori wards were set up.
Labour in 2022 abolished the requirement for local councils to hold a referendum on Māori wards, saying rural and other wards did not face that requirement.
The local body elections later that year included Māori ward candidates in 35 councils across the country, many for the first time.
The change had the support of Local Government New Zealand, whose president Sam Broughton said all wards should be treated the same - with councils themselves making the call.
However, coalition parties campaigned against the move and both the government's coalition agreements included a commitment to bring back the requirement for a referedum.
Brown took that a step further on in his statement on Thursday, saying councils that brought in wards under Labour's law would be required under new legislation to hold a referendum on the wards during the 2025 election. The results of those referedums would be binding and take effect from the 2028 local government term.
He said the other option for councils would be to scrap their Māori wards.
"If councils do not wish to hold a poll, those councils will be given the opportunity to reverse their decision to establish Māori wards or to disestablish those wards prior to the 2025 local body elections," he said.
"Local community members deserve to have a say in their governance arrangements."
He said the government would introduce legislation in the coming months, to be passed by the end of July.
The ACT Party celebrated the move, with leader David Seymour in a statement saying the decision should lie with "the communities themselves, not Wellington".
"Labour stripped democracy from local government by removing the ability to call for a local referendum on Māori wards, and the Government is restoring voters' voices," he said.
He also pointed to the reintroduction of a rule allowing at least 5 percent of a council's ratepayers to petition for another referendum on Māori wards on an ongoing basis.
Councils including Wairoa District, Waikato Regional and the Bay of Plenty Regional would not be affected as their Māori wards were set up before the removal of poll requirements.
Ōpōtiki District's wards would also not be affected as they were set up after voluntarily holding a poll at the 2022 elections, which was in favour.
Tauranga City Council - which has been under the management of commissioners - will hold early elections in July to elect councillors and will be able to either reverse its decision to introduce Māori wards or hold a poll in the 2024-2028 term, with the results taking effect after the 2028 election.