The number of people wanting to become New Zealand citizens dipped slightly last year, but applications from the United Kingdom, India and Philippines remained the most common.
Provisional figures released by the Department of Internal Affairs show the total number of citizenship ceremonies fell from 36,450 in 2017 to 33,791 in 2018 to early December.
To become a New Zealand citizen you need to have been a resident of the country for five years and pass other criteria.
Registrar-General of Births, Deaths and Marriages Jeff Montgomery said while there appears to have been a slight reduction in the number of new citizens, the drop wasn't statistically significant and there is at least a five-year lag from people arriving in New Zealand.
The provisional figures show a decrease in numbers from the top seven countries, including Samoa, South Africa, Fiji and China.
Only Tonga and Australia, which were ranked eighth and ninth, increased in citizenship numbers.
Mr Montgomery said those wanting to become New Zealand citizens did so for a range of reasons and may be joining family, studying or working.
He said people could apply to become citizens once they had been in the country for five years, but they didn't have to.
"The British take a very long time to apply. The average length of time that a Brit will have been in the country before they apply is much longer than, for example, a South African," he said.
"A South African will basically apply for citizenship as soon as they are able to because they want the New Zealand passport and the ability to travel to more country's visa-free than a South African passport.
"Whereas the British will wait much, much longer, usually until the old passport has expired before they'll seek New Zealand citizenship."
He said those kinds of things would impact when people would apply, as well as when and why people decided to migrate to New Zealand.
Mr Montgomery said citizenship ceremonies, which were run by the local council, continued up until Christmas Eve. The final citizenship figures are expected to be released this month.