Eifert agreed to a one-year deal with the Bengals, multiple media outlets reported Thursday, and NFL Network's Tom Pelissero reports that the contract carries a maximum value of $8 million.
Eifert, 27, has spent each of his five NFL seasons with the Bengals, but he has had trouble staying healthy.
He played in only eight games in 2016 and just two in 2017 because of a variety of injuries, including a back problem that required two surgeries. He was also limited to one game in 2014 when he dislocated his right elbow.
Eifert recently said he is healthy again, and if he stays that way he can provide an important weapon, especially in the red zone.
He caught five touchdown passes in just eight games in 2016 and had 13 touchdown receptions in 13 games during the 2015 season.
Eifert was a Pro Bowl selection in that 2015 season, when he had 52 receptions for 615 yards.
The Bengals also officially announced that they signed punter Kevin Huber to a three-year deal.
Huber, 32, has spent his entire nine-year career with Cincinnati since the team selected him in the fifth round of the 2009 NFL Draft. He was a Pro Bowl selection in 2014.