Gillies' early life and education were in Queenborough in Kent, England. His family moved to Brantford, Ontario, Canada when he was seven. Gillies attended elementary and secondary schools there. He completed his education at the University of Western Ontario and worked as an advertising executive.
The Progressive Conservative Party was reduced to a tenuous minority government following the 1985 provincial election. Gillies himself was narrowly re-elected in Brantford, defeating NDP candidate Jack Tubman by 1,141 votes.[5] He was promoted to Minister of Skills Development on May 17, 1985[2][6] but accomplished little before the Tories were defeated in a non-confidence motion in the house two months later.
In opposition, Gillies served as his party's critic for skills development, labour and the environment. Gillies took an interest in labour and human rights issues, and was one of the first PC MPPs to work for LGBT rights in Ontario.[7] He was defeated in the 1987 provincial election, finishing third against Liberal candidate Dave Neumann.[8]
Gillies ran communications and advertising for the Ontario Progressive Conservatives in the 1990 provincial election in support of new party leader Mike Harris.
After leaving politics, Gillies became a vice-president of the public relations firm Hill & Knowlton.[2] He later worked as a consultant for the Liquor Control Board of Ontario, the Royal Bank of Canada and other corporations and non-profit organizations,[2] and came out as gay.[9] He has served as a director of Orchestra London, the Brant Social Development Council, the Brantford Symphony Orchestra, and the Enos Foundation, the Public Affairs Association of Canada, the Toronto Mayor's Evening for the Arts and serves on the advisory council of ProudPolitics. Gillies has also served on committees for Autism Speaks Canada and TVOntario.
Gillies has published columns in the Toronto Star, Toronto Sun and Hamilton Spectator.
Gillies worked on endangered species issues for the WildAid Conservation Society in 2011 and 2012. In 2013 and 2014, he provided consulting services to the Patey Law Group, Accident Resolution Group, Canadian Centre on Substance Abuse, the Carpenters Union, Clean Prosperity and Toronto Expo 2025.
In 2011, Gillies helped spearhead a national campaign to have shark fin banned in Canada. He led his hometown of Brantford to become the first municipality in North America to ban the trade and possession of shark fin through a by-law passed on May 24, 2011.[10] This led to the introduction of similar legislation in Toronto, Oakville, Mississauga and other Canadian cities. These municipal campaigns led Canada's Parliament to pass legislation to ban the national shark fin trade. This became law in June, 2019.
Gillies ran as the Progressive Conservative candidate in Brant in the 2014 election,[11] but was not re-elected to the legislature.
In the summer of 2014, Gillies became Associate Director of Policy on the campaign of Toronto mayoralty candidate John Tory.
In January 2015, Toronto mayor John Tory named Gillies as secretary of the Mayor's Task Force on Toronto Community Housing, under the chairmanship of Senator Art Eggleton. In June 2016 Gillies joined Enterprise Canada Public Affairs as Municipal Practice Lead. At Enterprise, he has represented corporations including Enbridge Gas Distribution, Emovis Technologies, associations such as the Downtown-Yonge Business Improvement Area, and governments/public agencies including York Region, Peel Region, Halton Region, the City of Hamilton, City of Niagara Falls and Metrolinx.
In 2016 at the annual convention of the Ontario Progressive Conservative Party, Gillies was presented with a special achievement award by leader Patrick Brown for his decades of service to the party.
In 2018 Phil Gillies was appointed executive director of the Ontario Construction Consortium, a think tank supported by the unionized construction sector.
In 2023 Gillies was appointed a Director of Ontario One Call.