The days of discounted greenhouse gas emissions are coming to an end for businesses.

New Zealand companies now have to pay 83% of the cost of their carbon units, as part of changes to the Emissions Trading Scheme.

They previously paid only half price.

The subsidy deal was introduced during the global financial crisis to help businesses struggling with the cost of the ETS.

National's climate change spokesperson Todd Muller says businesses will pay full price next year, which will help this country achieve its pollution reduction targets.

"There are 192 countries signed up to the Paris Accord on climate change.

"Each country has their own journey that they will need to take to adjust over time to move their industries from carbon-intensive to less carbon-intensive."

Mr Muller said if businesses don't move closer to paying market price for their emissions, this country won't meet its 2030 targets.

"The either off-set that by buying a credit through the scheme, with forestry being a great example of where they can offset their obligations.

"In some cases, they can write out a cheque which reflects the current price of carbon in the market at the moment," he said.