McGillvary was born in Huddersfield, West Yorkshire, England, and he is of Grenadian descent. Jermaine is a product of the Giants' academy system.
Playing career
After signing for the Huddersfield Giants, McGillvary was sent out on loan to Batley Bulldogs for the 2009 Co-operative Championship, a season which saw him progress as a talent and earned him selection in the 2009 Championship team of the season. Batley/Batley Bulldogs' "most tries in a match" record of 5-tries, is jointly held by; Joe Oakland, Tommy 'Dowdy' Brannan, Jim Wale, Tommy Oldroyd, Ben Feehan, and Jermaine McGillvary. He made his first-grade début in 2010, starting on the right wing against Bradford Bulls in round 16 of 2010's Super League XV. In 2011 McGillvary was awarded the Albert GoldthorpeRookie of the Year Medal. On 4 May 2014 Jermaine made his 100th appearance for Huddersfield. Fittingly he scored a try in his team's crucial 1 point win over 3rd placed Super League team, the Castleford Tigers. McGillvary finished as Super League's top try scorer in 2015, with 27, and earned selection in the Super League Dream Team.
International career
McGillvary's was selected in Steve McNamara's 24-man England team for their test series against New Zealand. He made his début for England in the decisive final test-match at the DW Stadium. The following year, McGillvary was selected in the England squad for the 2016 Four Nations. Before the tournament, England played a test match against France in which McGillvary scored a try in England's 40-6 win. Following the 2017 season, McGillvary was named in Wayne Bennett's England squad for the World Cup in Australia. McGillvary played on the wing in England's 6-0 defeat by Australia in the 2017 Rugby League World Cup final. He finished the tournament with seven tries in five games and ran more meters than any other player in the tournament. In 2018 he was selected for England against France at the Leigh Sports Village. He was selected in England 9s squad for the 2019 Rugby League World Cup 9s. He was selected in squad for the 2019 Great Britain Lions tour of the Southern Hemisphere. He made his Great Britain test debut in the defeat by Tonga.