As a freelance journalist, Matt has written articles for The Times, The Guardian, The Observer, The Independent, Buzzfeed, The Sun, The Mail, The Express, The Telegraph and The People. He was a judge for the 2013 Costa Book Awards and the Polari First Novel Prize 2014 and continues to judge the South Bank Sky Arts Awards. He has been nominated for Stonewall's Writer of the Year award and in September 2017 was voted winner of Diversity in Media's Journalist of the Year award.
In October 2017 Matt crowdfunded his third novel The Madonna of Bolton, after receiving over 30 rejections from publishers, reportedly due to its gay protagonist and theme. The title reached its funding target in seven days, becoming Unbound's fastest-crowdfunded novel ever. Pledges came in from 28 countries, including Saudi Arabia and Sri Lanka, where homosexuality is illegal. The project was backed by celebrities including David Walliams, Mark Gatiss, Gok Wan, David Nicholls, SJ Watson, Lisa Jewell and Arlene Phillips. The Madonna of Bolton was published by Unbound in July 2018.
Cain is an ambassador for both Manchester Pride and the Albert Kennedy Trust, the UK's national youth LGBT+ homelessness charity. He's also a patron of LGBT History Month.