Emission unit trading

Emissions units are a type of currency that are traded through the New Zealand Emissions Trading Register.

Businesses in the New Zealand Emissions Trading Scheme (ETS) may surrender, earn or be allocated emission units.

The New Zealand Emissions Trading Register (the Register), is our national registry for emission units, including those owned by the Crown. The Register acts like a bank, but it holds emission units instead of money. Businesses must have an account in the Register to be able to own or trade emission units in New Zealand. 

Trading emission units

The New Zealand Unit (NZU) is the primary currency of the ETS. There are various emission unit types in the  Register.

Until 2015, the Register held units associated with offshore initiatives, known as ‘Kyoto units’, which were created under the Kyoto Protocol. Since 2015, these international units have not been permitted to be used for compliance purposes in the ETS.


The Register enables international trading. It connects to other official registries via the International Transaction Log (ITL) run by the United Nations Framework Convention on Climate Change (UNFCCC). The ITL reconciles international trading on a daily basis to ensure that the same unit is not being used in multiple registries.
As with a share registry, the Register does not record information about the price or financial value of emission unit trades, nor does it provide a mechanism for exchanging cash for units traded.

Find out more about the United Nations Framework Convention on Climate Change - UNFCCC website