Statistics New Zealand has released an updated iwi statistical standard, which will guide how to collect, organise and describe iwi information.
Stats NZ kaihautu Rhonda Paku said the new standards better reflected contemporary Māori needs.
"The review has been a carefully considered process at every stage, and I want to acknowledge everyone who has provided us with feedback and contributed to the discussions - from iwi, Māori, government agencies, councils, and the public - during consultation in 2016 and 2017."
The new standard will be used in the 2018 census and by other government agencies collecting iwi information in survey, administrative and other data collections, Ms Paku said.
"Iwi statistics using the standard help iwi, government, and other organisations in planning, monitoring, and decision-making."
Ms Paku said it was expected the changes would result in more data becoming available for and about iwi and iwi-related groups.
Key changes include new conditions for including iwi in the classification, an updated purpose, and new approaches for reporting iwi information.
The standard also includes an updated and more inclusive classification of iwi and iwi-related groups.