Yankees manager Joe Girardi confirmed Bell's signing before New York played at Oakland on Friday night. Bell will report to Triple-A Scranton/Wilkes-Barre.
"This guy has had success, he's been a closer who has pitched in high-level situations," Girardi said. "We'll see if he can help us."
Bell was released by Tampa Bay on May 4 after going 1-1 with a 7.27 ERA in 13 appearances this season. The Rays acquired Bell from Arizona in December as part of a three-team trade.
Bell has 168 saves in 11 seasons with the New York Mets, San Diego, Miami, Arizona and Tampa Bay. He led the majors with 132 saves for the Padres from 2009 to '11.
Information from ESPNNewYork.com's Wallace Matthews and the Associated Press was used in this report.