GTHA emissions rise again, gap widens despite proven solutions

Carbon emissions in the Greater Toronto and Hamilton Area increased by 1% in 2024, from 54.1 million tonnes to 54.7 million tonnes

The 2024 Carbon Emissions Inventory for the GTHA shows that carbon reduction efforts are not happening at the pace and scale needed to hit 2030 targets, which would require 11% reductions per year. Yet, while the population increased by 300,000, per capita emissions decreased by 3%, proving that some progress is being made.

Increases were seen across all regions of the GTHA in 2024, with the exception of a minimal decline in Peel. While the industrial sector experienced a slight drop, emissions rose in every other sector of the economy.

With mounting pressure on governments to address economic challenges, now is the time to prioritize actions based on their ability to deliver carbon reduction and economic opportunities at once. Policymakers and elected officials can leverage this data to understand the sources of emissions, what’s working to mitigate them, and use insights and recommendations from this inventory to educate the public and provide evidence-based rationale and direction for their climate plans and programs.

Buildings are the number one source of urban emissions

Emissions from buildings make up 45% of all GTHA emissions and predominantly come from natural gas used for space heating and natural gas plants used for generating electricity. Building emissions increased by 1.7%, or 0.4 megatonnes, in 2024. Natural gas consumption decreased in commercial and residential sectors, while consumption in the industrial sector increased. Commercial and residential reductions are partly due to a warmer winter, and partly a result of efficiencies gained through growing momentum for retrofits, underscoring the importance of sustained funding programs like the oversubscribed Canada Greener Home Grant and local supports like the Durham Greener Homes Program. (The federal government cancelled the Canada Greener Homes Grant in 2025.)  

Natural gas plants are continuing to make the electricity grid more carbon intensive

Electricity emissions increased 28% in 2024 due to increased use of natural gas plants for generation, which has caused emissions to double since 2020. The use of this fossil fuel for electricity generation has eroded many carbon reduction successes over the last several years. Electricity emissions are forecast to continue increasing significantly over the next five years, undermining electrification and carbon reduction efforts in other sectors. There is an opportunity to change course and realize significant carbon reduction through fuel switching if Ontario commits to meeting growing electricity demand with non-emitting generation and cost-effective distributed energy resources on the near and long-term horizon.

Transportation emissions rose in most regions, accounting for over a third of GTHA emissions

Emissions from transportation make up 37% of all GTHA emissions and are caused mostly by personal vehicle use. While the rate of increase has slowed down significantly, total transportation emissions increased by 1% in 2024. Transit and active transportation, electric vehicle (EV) adoption and infrastructure, and designing smart communities will all be essential tools to deeper reductions.

Local sector-specific progress reveals climate action works

It's concerning that total emissions are going up when they need to steeply decline. But reductions in per capita emissions reveal that local climate actions are bending the curve. Per capita transportation emissions declined in every region, from a 2% reduction in Halton to a nearly 6% reduction in Peel. Transit ridership and EV purchases grew for a consecutive year. The population increased by over 300,000 people, but efficiency gains meant building emissions did not increase proportionally.

These results demonstrate which solutions are working and where governments should double down. Strengthening green building standards, supporting retrofits and adoption of distributed energy resources like solar, and accelerating EV adoption are tangible actions that get results. Unfortunately, declining federal and provincial support—and in some cases, active interference—are leaving local governments on the hook to drive climate action. Senior governments must increase climate investments and policies to bolster the efforts shown by leading municipalities.

TAF’s carbon inventory for the GTHA charts progress and makes recommendations for action by municipal, provincial, and federal governments, and the private sector. Check the status of GTHA municipalities in our updated policy tracker or skip to the recommendations for policymakers.

The GTHA represents 46% of Ontario’s emissions

The Greater Toronto and Hamilton Area (GTHA) in Canada includes the City of Toronto, the City of Hamilton, and the regional municipalities of Halton, Peel, York, and Durham.

This 8,241 square kilometre urban region, home to over 7.9 million people, is Canada’s commercial, distribution, and financial core —Almost half of Ontario’s emissions come from this region.

TAF acknowledges these boundaries were created by settlers and do not reflect the Indigenous peoples who have occupied these lands for thousands of years or their traditional territories or treaties.