The Remuneration Authority sets the annuity for former Governors-General and their surviving spouses.
Information on the current annuity for former Governors-General and spouses is in the following determination:
Governor-General (Annuities) Determination 2024 – New Zealand Legislation(external link)
The Governor-General Act 2010, s.8, s.9 provides that:
Governor-General Act 2010 - NZ Legislation(external link)
The annuity is reviewed every year and adjusted as appropriate.
For more background see the 2009 Law Commission’s Review Report on the Civil List Act 1979 the Governor-General, which was published on 17 December 2009.
Report on the Civil List Act 1979 - Law Commission(external link)