The stars became friends when they were both unknown singers, and The A Team hitmaker gave his pal a helping hand by taking him on tour after finding fame himself.
Passenger, real name Mike Rosenberg, has now scored a huge worldwide hit with his new album All the Little Lights, and he has thanked Sheeran for giving him his big break.
Speaking to Sarah Champion of Britain's Absolute Radio station during the Hard Rock Calling festival in London, he says, "We've been mates for about five years. We met when we were on the same bill at a local gig and really liked what each other were doing. When Ed got massive he took me on tour with him and changed my life. I love him - he's a wonderful guy"