Ontario has successfully implemented its policy to put an end to coal use in 2014. This energy transition has become “the single largest GHG reduction measure in North America”: since 2007, when coal accounted for about 25 per cent of its electricity generation, Ontario has reduced its greenhouse gas emissions by approximately 34 Mt or 17 per cent. What lessons can be learned from Ontario’s coal phase-out experience? How can its success be replicated in other parts of the globe? This paper explores this question for all those around the world who may draw inspiration and lessons learned from Ontario: policy-makers, campaigners, entrepreneurs and others interested in transitioning to a low-carbon future.