The 25-year old Victorian will transfer to the Swiss-based team joining fellow Australians David Tanner and 2015 road champion, Heinrich Haussler.
While a formal announcement of the 2016 team structure is yet to be released, IAM have confirmed that Vegard Stake Laengen and Oliver Naesen will also be joining the team for the 2016 season.
Together with Laengen and Naesen, Howard will bolster IAMs sprinting prowess.
"For next year, we want to have our pack of wolves a bit more compact and prominent at the front of the peloton in order to usher our sprinters to the finish line more effectively," said the team's founder Michel Thétaz, according to CyclingNews.
Howard has raced with Orica-GreenEDGE since the Australian-based WorldTour team began in 2012. He raced with HTC-Highroad from 2010-11.
Having made the transition to road cycling after a successful early career on the track, Howard has been a key part of Caleb Ewan’s lead out team in 2015. His best personal result this year was a sixth place finish at the 200km one-day event, the Prudential RideLondon and Surry Classic.