Tansey, 32, has played in the top-flight for Leeds Rhinos, Hull, Crusaders, Castleford Tigers, Wakefield Trinity and Huddersfield Giants.
He also had a stint in the NRL with Australian club Sydney Roosters and was at Workington Town last year.
Tansey said: “I’ll bring some experience to some of the young lads in the backs, because I’ve been playing for ten years now.
“In that time there’s been a lot of highlights, like being part of the Leeds squad when we won Super League and making my debut in Australia.
“Now I’m looking to help Featherstone get up near the top and have a few highlights here.”
The utility-back, who has also played for Dewsbury Rams and York City Knights, is keen to get back into the sport after taking some time outy.
He added: “There’s been loads of different factors which have prevented me getting to my best level over the past couple of years, but I’m glad to have this fresh start and excited to get going.
“I’m going to put 100 per cent in, to get back to my peak level.
“I’m 32, but I feel 26. I’ve still got plenty of running left in the legs and I can’t wait to get stuck into pre-season.”