The Green Party of Ontario (GPO; , PVO) is a political party in Ontario, Canada. It has run candidates in every Ontario election since 1985, and has contested every riding in elections since 2007.
The party's support peaked in the 2007 election at 8% of the popular vote, but dropped in the following election in 2011. In the four general elections since, its vote share has hovered around the 5% level. In the 2025 election, Green Party candidates were elected in two ridings.
The party is led by Mike Schreiner, who has represented the riding of Guelph since he first won election there in 2018 and became his party's first member of the Legislative Assembly of Ontario. The party gained a second MPP when Aislinn Clancy won the 2023 Kitchener Centre byelection. She held on to the seat in the 2025 general election.
In mid-1983, inspired by the electoral success of the Greens in West Germany, a small group of Ontarians launched a provincial Green Party. Starting with around 40 members and informally led by Dr. Trevor Hancock, the fledgling party began to develp a platform and sought to gather the 10,000 signatures necessary for obtaining official party status.
By the following year, their petition had been endorsed by 11,665 eligible voters, and on 4 July 1984, the Green Party of Ontario was approved by the Ontario Commission on Election Contributions and Expenses, bringing the number of registered parties in Ontario to eight. The party could accept contributions and issue tax receipts, and was the second green party to be registered in Canadathe Green Party of British Columbia having been registered the year before. (The Green Party of Canada was registered federally a month later).
With nine chapters and nearly 500 members, the Green Party of Ontario was described as being pro-peace, pro-environment, and cutting across the political left and right. Hancock was nominally leader, but the party platform rejected centralized power.
In 1985 the party contested its first election, fielding nine candidates who collected a combined 5,345 votes or 0.15%. In the 1987 election the party ran seven candidates who fared worse, collecting 3,398 votes or 0.09%. In 1990, the party achieved a higher result, with 40 candidates capturing 30,097 votes or 0.75%.
Frank de Jong became the party's first official leader in 1993. In the next general election, in 1995, the party lost more than half its previous support, with 37 candidates receiving 14,108 votes or 0.34%.
The party regained its earlier level of support in the 1999 election when 58 candidates received 30,781 votes or .70%.
The 2003 election saw an even more dramatic increase in vote share for the Greens. Running 102 out of a possible 103 candidates, the party captured 126,651 votes, or 2.82%. The GPO placed ahead of the NDP in two ridings, and took fourth place in 92 others.
At the party's 2006 annual general meeting, constitutional changes were made, such as requiring gender-paritied representatives from each of six regions, gender-paritied deputy leaders, and the creation of multiple functionary roles separated from the provincial executive. One of the first acts of the new provincial executive was to strike a hiring committee to bring on a full-time campaign manager to ensure election readiness.
In the 2007 election, still under de Jong's leadership, the party fielded a full slate of 107 candidates, receiving 354,897 votes or 8.02%. In the run-up to the election, opinion polls showed the Greens' support climbing into the double-digits for the first time in party history.
Although no Greens were elected in 2007, the party almost tripled its 2003 vote share, placed second in one riding (BruceâÂÂGreyâÂÂOwen Sound, with 33.1% compared to the PC incumbent winner's 46.7%), and took third place in a number of other ridings. Shane Jolley, the Green candidate for Bruce-Grey-Owen Sound, earned more votes than any Green candidate in Canadian history at that time.De Jong announced his resignation as leader on 16 May 2009 at the annual general meeting. A leadership and policy convention was held 13âÂÂ15 November 2009 in London, Ontario, and Mike Schreiner, a Toronto entrepreneur who was the sole candidate, became the party's new leader.
The party's popularity sank back to 2003 levels in the 2011 election, a tightly contested race between the Progressive Conservatives and ruling Liberals. In the 2014 election the party regained some ground and received 233,269 votes or 4.84% province-wide, and Schreiner picked up 19% of the vote in his riding of Guelph. But the Greens had yet to win a seat in the legislature.
In the 2018 election, their third with Mike Schreiner as leader, the party ran on a platform of investing in green jobs and clean energy, rolling out a universal basic income, and investing in mental health services. The party ran a full slate of candidates including over 50% women for the first time. Schreiner was excluded from the televised leaders debates, which led to an unsuccessful campaign by Fair Debates to encourage media to reverse the decisions.
In May 2018, a month ahead of that year's general election, the Toronto Star editorial board endorsed Schreiner as the best candidate in Guelph and said that he was "the most forthright leader in the campaign for the 7 June Ontario election." Schreiner was also endorsed by the Guelph Mercurys editorial board in an op-ed, "Mike Schreiner is the candidate most worthy of representing Guelph provincially," citing ten reasons to vote for Schreiner.
Schreiner's campaign proved successful, and he was elected as the first ever Green MPP in Ontario history. He captured 45 per cent of the vote in the Guelph riding, more than doubling the previous percentage and nearly tripling his raw vote numbers.
Schreiner was re-elected in the 2022 provincial election and was again the only Green candidate elected. The party narrowly lost in Parry SoundâÂÂMuskoka, a riding that had been held by the Progressive Conservatives since its establishment in 1999. Green candidate Matt Richter placed second to PC candidate Graydon Smith, losing by just over 2,100 votes.
The party elected its second MPP in 2023. Green candidate and deputy leader Aislinn Clancy was elected in a 2023 by-election in Kitchener Centre, doubling Green representation in the Legislature. Clancy won just under 48% of the vote, solidly beating the NDP candidate. The seat had previously been in New Democratic hands since 2018.
The Green Party of Ontario shares the values identified by the Global Greens: participatory democracy, nonviolence, social justice, sustainability, respect for diversity and ecological wisdom. The party describes itself as socially progressive, environmentally focused and fiscally responsible.
In the lead-up to the 2022 election, the party released policy papers focused on housing, climate change and mental health. Its 2022 platform identified three priorities: a caring society, focussed on improving equitable healthcare, education, and social services; connected communities, focussed on tackling housing affordability by building more infill development, strengthening protections for renters and addressing speculation in the housing market; and new climate economy, focused on achieving net-zero emissions by 2045 by replacing fossil fuels with renewable energy sources, growing green jobs and protecting the environment.
The party advocates for more permissive zoning laws that allow the construction of missing-middle and midrise housing. It argues that infill development is more environmentally friendly and cost-effective than sprawl development.
Its elected members have also called for more stringent tenants protections and for the province to partner with non-profit and co-operative housing providers to build affordable non-market homes.
The party's housing plan, released in 2021, featured seven strategies to build what the party referred to as "more liveable and affordable communities." They included building more inclusive neighbourhoods through missing middle and midrise development, protecting farmland and other natural land from urban sprawl, building and maintaining a provincial affordable housing supply, ending chronic homelessness, strengthening protections for renters and addressing speculation in the housing market. The Toronto Star editorial board endorsed the plan, referring to it as "an ambitious document that proposes tackling the housing crisis from all vantage points."
The Green Party supports phasing out fossil fuels and moving to renewable energy sources. Its platform included a number of measures to increase the affordability and accessibility of electric vehicles, retrofit homes and businesses to increase energy efficiency, and phase out fossil fuels to reach net zero by 2045.
The party was opposed to the construction of new nuclear plants. However, in November 2024, the party formally reversed its position on nuclear energy at its Annual General Meeting. Party delegates passed a resolution recognizing nuclear power as a low-emission energy source and supported the use of Canadian-designed CANDU reactors as part of OntarioâÂÂs electricity mix. It has also called for an end to the province's offshore wind moratorium in order to increase access to renewable power.
Greens advocate for stronger protections to wetlands and agricultural land. Party leader Mike Schreiner was vocal in opposing the Ford government's plan to allow development on southern Ontario's Greenbelt, which was ultimately reversed in 2023.
The Greens' healthcare policies are rooted in prevention, including increasing upstream investments in the social determinants of health like social isolation, housing insecurity and poverty, as well as partnering with the federal government to implement universal pharmacare and dental care programs. The party advocates for improving the recruitment, retention and safety of public healthcare workers. It supports a publicly funded, publicly delivered healthcare system and opposes the privatisation of healthcare services.
The party supports a non-profit long-term care system and has called to phase out for-profit long-term care homes while increasing base funding for the sector. In its 2022 platform, the party pledged to build 55,000 long-term care beds by 2033 and at least 96,000 by 2041.
In 2022, the party released a mental health policy paper calling for the expansion of access to mental health and addictions care under OHIP and an immediate base budget increase of 8% to the community mental health sector.
The party's education platform includes updating OntarioâÂÂs funding formula to reflect evolving student needs, including adequate funding for special education and rural and remote schools.
The party supports in-person learning and opposes mandatory e-learning or hybrid learning models. It has called for the elimination of EQAO standardised testing.
In the 2022 provincial election, the party pledged to cap elementary classroom sizes at 24 students for grades four through eight and at 26 students for kindergarten.
At the postsecondary level, the party has called to increase sector funding by indexing the base operating grant for Ontario's postsecondary institutions to the weighted national average.
Its 2022 platform called for the reversal of OSAP funding cuts through the conversion of loans to grants for low- and middle-income students and the elimination of interest charges on student debt.
During the 2007 provincial election, education, and specifically the funding of religious schools, was a central issue. GPO policy calls for an end to the publicly funded Catholic school system, a merger that it claimed would save millions of dollars in duplicate administrative costs.
The Green Party of Ontario believes in modernizing the social safety net to account for present-day challenges. Greens have advocated for the doubling of the Ontario Disability Support Program and Ontario Works.
It has been an advocate for a universal Basic Income for all Ontarians, in order to provide economic security while at the same time cutting red tape and bureaucracy.
The party supports ten-dollar-a-day daycare. In its 2022 platform, it pledged to work with the federal government to ensure continued funding for universal access to ten-dollar-a-day care.
During the COVID-19 pandemic, Green party leader Mike Schreiner called for an increase in the number of provincially legislated sick days from three to ten and for a ban on employers requiring sick notes from employees who take time off due to illness.
The GPO is a strong supporter of electoral reform. In its 2022 election platform, it called for the creation of a "diverse, randomly selected Citizens Assembly on electoral reform" to provide recommendations on how to modernise the Ontario electoral system to better reflect voters' democratic will.
Greens have historically supported tax relief for small businesses, generally funded by modest increases to the corporate tax rate. They have also proposed road pricing (including tolls, parking levies and land-value taxes near subways) to pay for public transit.
The party has proposed a number of tax measures to reduce speculation in the housing market, including a multi-homes tax on all individuals and corporations owning more than two residential properties, a vacant homes tax and an anti-flipping tax.
The party favours a revenue neutral carbon fee-and-dividend approach to pollution pricing. In its 2022 platform, it proposed to take over federal administration of the carbon pricing system, increasing the price by $25 annually until it reaches $300/tonne and returning all revenues collected from individuals to individuals as dividends.