Leinster back Noel Reid, Newcastle lock Calum Green and Munster centre Jaco Taute will join Premiership club Leicester at the end of the season.
Reid, 28, who can play at centre or fly-half, won an international cap for Ireland against Argentina in 2014.
Green, 28, came through Leicester's academy and the lock has played 120 games during five seasons at Newcastle, the Premiership's bottom side.
South Africa international Taute, 27, has been with Munster since 2016.
Reid told the Tigers' website: "I'm very excited to be joining a club like Leicester, with its history and success in the game."
Green added: "To have the opportunity to return was too good an opportunity to let go by.
"I know a lot of the players in the squad, coaches and staff and am excited to get back to Welford Road and be called a Tiger once again."
Leicester are 10th in the Premiership but almost safe from relegation - they are eight points ahead of Newcastle with three games left to play.