The 28-year old has been on the hunt for a new club since he was released by the Trotters at the end of last season and will now suit up for Paul Jewell's Championship outfit until January.
Despite Ipswich sitting second bottom on the second tier table, Reo-Coker is excited about his stint at Portman Road.
"Ipswich is a sleeping giant in the Championship," Reo-Coker told the club's official website.
"It's a massive club with a great history and tradition. The facilities are first class and there is a terrific fan base. It's the right club at the right time for me and everything has just fallen into place.
"I had a good conversation with the manager. He's highly respected in the game for what he has achieved and I know what he's trying to do at the club.
"Ipswich may be at the wrong end of the table at the moment but it's still early in the season and I'm sure with the manager and players the club have, it's only a matter of time before things turn around."