Jag Mangat began his modelling career in 2004 when he was noticed downtown Vancouver. Later that year he did his first runway for Temptation 2004 featuring Sharukh Khan in front of 15,000 people. Between 2005 and 2008 Jag was featured in various magazines and runway modelling. Also he started his acting debut while doing background for Fantastic 4 and various other short films and tv films.

In 2004 Jag was featured in Jaag Jeyonda de Mela featuring Harbhajaan Mann. Jag played the role of Terry in this film.

In 2010 won the first most eligible south Asian bachelor of Canada. In 2011 Jag was featured in a 7 page spread as the bachelor of the year in Asian Women Magazine.