Mattamy Homes is a Canadian home builder, founded in Toronto by Peter Gilgan in 1978. One of the largest privately owned builders in North America, Mattamy Homes is Canada's largest residential home builder and top-25 builder in the United States. 
The company's name is a portmanteau of the names of Gilgan's two oldest children, Matt and Amy. 
Notable neighbourhoods and communities developed by Mattamy Homes include:
- Hawthorne Village, Milton, Ontario
- Mattamy on Main, Whitchurch-Stouffville, Ontario
- Berczy Village, Markham, Ontario
- Parkside Towns at Saturday in Downsview Park, North York, Toronto, Ontario
- Wellen Park, North Port, Florida
In 2015, Gilgan donated $5-million to Parks Foundation Calgary to be used for the development of a 138-kilometre ring of paved pathways around the city. The creation of the Rotary/Mattamy Greenway began in 2010 and was completed in 2017. 
In North Port, Florida, Mattamy donated 90 acres (36 ha) of land along with $4.7 million towards the development of the new CoolToday Park, a ballpark and spring training complex for the Atlanta Braves which opened March 24, 2019 against the Tampa Bay Rays. 
Prior to the 2018 Ontario general election, Mattamy Homes donated $100,000 to Ontario Proud, a right-wing political advocacy group which used television ads and Facebook to support Doug Ford and the Progressive Conservative Party of Ontario. Of the $460,000 raised by Ontario Proud, most was donated by developers "who wanted Ford to ease environmental rules for housing developments". The donation, controversial due to Ontario's recent prohibition of political donations to candidates from corporations, was the subject of broad media coverage, including in the CBC, Global News, and the Globe and Mail, and the legitimacy of the donation was questioned by the Canadian Medical Association Journal. Mattamy was forced to release a public statement addressing the donation, and pledged to make no contributions to political advocacy groups in the future.
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