Emissions returns and mandatory emissions return periods in the ETS

About mandatory emissions return periods (MERPs)

Mandatory emissions return periods (MERPs) are periods of time set in the ETS legislation. MERPs provide the framework for submitting regular reporting about the carbon in post-1989 forest land. If you have post-1989 forest land in the ETS, you:

• must submit an emissions return after the end of each MERP
• have the option to submit provisional emissions returns during MERPs.

On this web page, we explain when and how to submit these emissions returns.

More about emissions returns for forest land in general

Other emissions returns submitted when certain situations change

Emissions returns due at the end of MERPs

If you are registered in the ETS with post-1989 forest land at the end of a MERP, you must submit an emissions return.

You may have previously known this kind of emissions return as a “mandatory emissions return (MER)”. It’s also known as a “final emissions return” in the ETS legislation.

The units received or to be surrendered for each MERP will be based on the changes in forest carbon reported in your emissions return for that MERP. You cannot claim units for previous MERPs.

How to submit an emissions return after the end of a MERP

Dates for when to submit emissions returns due at the end of mandatory emissions returns periods

Provisional emissions returns submitted during MERPs

You can submit emissions returns during a MERP after the end of each calendar year. This is optional.

This type of return was previously known as a "voluntary emissions return (VER)". From 1 January 2023, it will be known as a "provisional emissions return".

Provisional emissions returns are submitted by 1 July in the year following the year that the return ends.

You cannot submit a provisional emissions return at the end of a MERP.

How to submit a provisional emissions return during a MERP

One-off emissions return when moving from stock change accounting to averaging accounting

If your post-1989 forest land entered the ETS from 1 January 2019 to 31 December 2022, you’ll be registered automatically under stock change accounting. Stock change accounting is how the units for the carbon on your land are calculated. This means that as your forest grows and is harvested, you’ll earn and surrender units.

In 2023, a new carbon accounting approach called averaging accounting will be available for this land. Averaging accounting means you’ll earn units differently. You’ll only earn units for your forest land until it reaches an average age, from:

• when it was first established, if established during the MERP, or
• from the beginning of the MERP, if the forest was established before the MERP began.

Find out more about accounting for carbon in the ETS

In early 2023, you’ll have a one-off opportunity to move to averaging accounting for your post-1989 forest land. This only applies to the areas of land (known as carbon accounting areas) that entered the ETS from 2019 to 2022. You can choose to move some or all of this land to averaging accounting.

If you decide to do this, you must tell us by 30 June 2023. You must first apply to change to averaging accounting for those areas of forest land. Once this is confirmed, you’ll submit a one-off emissions return for the land for the 2018–2022 MERP. You’ll use averaging accounting to calculate the carbon in this emissions return.

The application form to move to averaging accounting is now available.

Read more about changing to averaging accounting or apply to change

Find out more about the differences between calculations for stock change and averaging accounting

The emissions returns to submit in 2023 for the 2018-2022 MERP will depend on what land you have in the ETS. Use this table to help you.

How to submit emissions returns during and following MERPs

Use the ETS online system, Tupu-ake to submit:

• an emissions return at the end of a MERP
• a provisional emissions return during a MERP.

ETS online system

Your emissions return must include information about how the amount of carbon in your post-1989 forest land changed over the time covered by the return. You’ll report on this for each carbon accounting area in your forest land.

When you submit your emissions return using the online system, Tupu-ake, you’ll have 2 options for completing the calculations for the change in carbon in your forest.

Use Tupu-ake to calculate your emissions return

Tupu-ake can calculate your emissions return, based on the information in the system. This calculation is also known as an “input return”. If you are using Tupu-ake for these calculations, you must update your forest information in the system, to identify and map areas of harvested or newly planted forest. You’ll then tell the system to perform the calculations for your return. This will take a few minutes.

The deadline for completing this is 7 days before the deadline for submitting your emissions return. If you miss this deadline, you’ll complete your calculations outside of the system.

Calculate your emissions return and upload the calculations

Using the calculations generated by Tupu-ake is optional. You can choose to complete the calculations for your emissions return outside the system. You’ll upload these calculations to Tupu-ake when you submit your emissions return.

Find out more about calculating forest carbon for emissions returns

Calculating your end-of-MERP emissions return when you submitted provisional or other emissions returns during the MERP

Make sure you don’t report the changes in carbon in your forest for the same area twice. When preparing your end-of-MERP emissions return, you must take into account for each carbon accounting area:

• any emissions returns processed during the MERP
• any units earned or paid (surrendered) during the MERP.

Emissions returns processed during the MERP include:

• provisional emissions returns
• other emissions returns where you have already reported forest carbon changes, for example, after removing a part of a carbon accounting area from the ETS.

If you submitted provisional (voluntary) emissions returns during a MERP

If you submitted 1 or more provisional emissions returns during a MERP, you must take these into account when you submit your emissions return at the end of the MERP.  Before 2023, provisional emissions returns were known as voluntary emissions returns or VERs. This applies to VERs too.

If you are calculating emissions returns for the end of a MERP outside of our ETS online system, Tupu-ake, you should:

• calculate and provide the carbon changes in the forest for the whole MERP
• calculate the units you’ll receive or have to pay (surrender) for the whole MERP
• take into account any units you received or paid for provisional/voluntary) returns during the MERP.

This means:

• if you earned units after submitting provisional/voluntary returns, you’ll subtract these from the units calculated for the whole MERP
• if you paid units after submitting provisional/voluntary returns, you’ll add these to the units calculated for the whole MERP.

If you registered, established, added or removed forest land during a MERP

Carbon accounting areas within your emissions return may have different start dates for their return periods. The end date will always be the same - the end of the MERP. (Carbon accounting areas are chosen when the land enters the ETS).

Use this table to work out what to include in your emissions return if you:

• registered in the ETS
• added more land partway through a MERP
• removed land from the ETS. 

What your end-of-MERP emissions return will cover if you registered in the ETS partway through a MERP, or added or removed land