More than 30,000 people are waiting for their citizenship to be approved after a blowout in processing times.
The introduction of an online system and COVID-19 restrictions are being blamed for waiting times of up to a year - despite applicant numbers falling last year.
Government figures show 94,000 people have applied for citizenship since 2019, but only 64,000 have been approved. That includes citizenship granted to immigrants after at least five years of residence, and citizenship by descent, for overseas-born children of New Zealanders.
Citizenship by grant now takes 10-11 months to be looked at by a case officer and another one to two months to be decided after that. Citizenship ceremonies add another two or three months to the process, although they are suspended during the current outbreak.
Internal Affairs said it was focused on speeding up the process and it expected to reduce the backlog by the middle of next year.
It has taken on new staff and retrained employees who would usually issue passports.
So far this year, 26,000 people have applied for citizenship, and 11,700 were approved.
Case officers were first picking up a citizenship application five months after it was submitted, compared to a fortnight two years ago.
Internal Affairs said in a statement it understood delays in citizenship decisions impacted people.
"We have prioritised this backlog and created a specific programme of work to improve it," said its general manager of service and access, Julia Wootton. "This includes more training, investing in technology changes to speed things up, establishing a temporary workforce dedicated to working though people's applications.
"We are confident that the steps we have taken mean we will have the skills and processes in place early next year to ensure we can slow the backlog and begin to reduce it by mid next year."
Staff were working hard to get back to much shorter timeframes after disruption caused by a 'realignment' of the department's life and identity services in 2019, she said.
"There has been an increase in processing times for citizenship applications over the past 12-24 months as we move to a new citizenship processing system that incrementally improves citizenship services and is being built and introduced in stages. Until that is fully in place we are working in both the old system and the new. This system moves us from a manual paper-based system to an online system.
"COVID-19 lockdowns have affected our ability to deliver these services. Our citizenship system, which holds highly secure and privacy protected data about individuals and their families, is only accessed from our security-controlled offices. Citizenship is not considered an essential service so while the country or various regions are at alert level 4 or 3, we have limited staff on site delivering essential services only."
Thirty new staff since July last year included 11 full-time employees and staff who could process passport or citizenship applications depending on demand. More staff were being added this month, Wootton said.
"A team of temporary staff has been brought on to process the approximately 9,000 cases that remain in our old system, freeing up existing staff to increase proficiency and speed in using the new system," she said. "The new system gives us better data on applications, and enables us to adopt new ways of processing, including automating some assessments. We will soon roll out a feature which enables applications to be routed to appropriately skilled officers, depending on their complexity. These and other changes based on analysis of application trends will help us process more quickly."
How many people applied for citizenship
2019 - 35,274
2020 - 32,030
1/01/2021 - 22/09/2021 - 26,673
How many people had their citizenship approved
2019 - 31,710
2020 - 20,488
1/01/2021 - 22/09/2021 - 11,719