The 25-year-old will fly out to Sydney in the next two weeks, as he looks to launch his career in Australia.
RFL Match Officials coaching and technical director Jon Sharp believes that Roby will do well Down Under.
“This is a fantastic opportunity for Tim, I have no doubts that he will do extremely well in Australia and we wish him all the best in his new career,” he said.
“Tim is a product of our development programme and his move to Australia is an indication of the high regard in which our match officials are held around the world.
“There are some outstanding young officials emerging through that same development programme and Tim’s departure gives them a chance to realise their ambitions of refereeing at the highest level.”
Roby has been the man in the middle at over 75 Super League games over the last five years, and has also worked as a touch judge at many big games, including two Challenge Cup finals and the 2014 Super League Grand Final.
He also worked at the 2013 Rugby League World Cup.
“It’s always been my ambition to officiate in Australia and my partner and I are hugely excited that this opportunity has arisen,” said Roby.
“I expressed an interest with the NRL some time ago and I am fortunate enough to have been offered a contract on the back of that.
“I would like to thank the RFL for the last five years; it’s been a great privilege to be part of the senior match officials team and I am going to miss working with some terrific people. I wish everyone here in the British game the very best for 2015.”