Date of birth data standard [PDF 286 KB]
The purpose of this standard is to mandate 'ISO 8601 - 1:2019, Date and time — representations for information interchange — part 1: basic rules', to be used to format date of birth for sharing purposes.
This mandated standard applies to data being shared between organisations.
This mandated standard does not mandate the collection or storage of date of birth. These may vary depending on the needs of the organisation.
ISO 8601 - 1:2019 Date and time — representations for information interchange — part 1: basic rules
Date of birth is the localised year, month, and day a natural person was born.
The minimum required format for compliance when sharing date of birth information is YYYY-MM-DD (or YYYYMMDD).
ISO 8601 Date representation and format examples:
While this standard does not mandate how date of birth data is collected or stored in databases, guidance on the collection of date of birth can be found in the 'Statistical standard for age'.
The date at the location of birth is to be used and not adjusted for any time zone offsets.
When a date of birth is not recorded a default date should not be used to indicate this. Instead do not supply any date.
The mandated standard does not require date of birth to be verified, but if it is this may be useful information to be noted when shared.
Document ID: DCS-002-00
Document version: 1.0
Approval date: 12/12/2019
Effective date: 02/04/2020
Review date: 02/04/2021
This document was created by a cross public sector working group which was led by Stats NZ. For more information please contact MandatedStandards@stats.govt.nz.
This work is licensed under the Creative Commons Attribution 4.0 International licence. In essence, you are free to copy, distribute and adapt the work, as long as you attribute the work to the Crown and abide by the other licence terms.
To view a copy of this licence, visit https://creativecommons.org/licenses/by/4.0/.
If you’d like more information, have a question, or want to provide feedback, email MandatedStandards@stats.govt.nz.
Content last reviewed 14 February 2022.