The 2018 Census was a modernised census based on models used in 2016 by the Canadian and Australian statistical agencies and then applied in the New Zealand context. Stats NZ collaborated with census experts from both countries when designing the model.

Under the new model, how Stats NZ enabled/collected from the respondents changed from predominately field-based activities to 80 percent mail-out with a reduced field presence and increased communications, marketing and engagement. The way respondents completed their forms also changed, with a greater focus on online completion over paper. The majority of the population was encouraged to complete the census online using an internet access code mailed to their households before census night. The new collection model therefore relied on the public to self-respond, rather than wait for a visit from field staff. Field follow-up activities were also planned.

The main areas of change were:
- phasing the model (prepare, enable, remind and visit)
- strategies used across the different phases
- mailing out “call to action” letters with an internet access code and instructions on how to order paper forms, if required, as the first interaction with census
- reducing the number of field staff, with a new structure and roles
- outsourcing the recruitment functions for field staff
- introducing new field technology
- creating a new address frame (a list of all dwellings in New Zealand)
- an integrated communications campaign including community engagement
- a new approach to processing the census data.