The 29-year old signed for the Ospreys in the summer of 2011 from Bath and has played 86 times for the region to date, as well as winning 16 caps for Wales.
Speaking about his move to the T14 club, Jarvis said: “I’ve really enjoyed my time with the Ospreys and am proud of everything we’ve achieved over the last five years.
“There’s still a job to do this season though and I’ll be giving it everything to ensure I finish on a high before moving on to a fresh challenge with my new club.”