The Tampa Bay Rays 2018 season was the Rays' 21st season of Major League Baseball, and the 11th as the "Rays" (all at Tropicana Field). The Rays played this season with few starting pitchers. Many games were started by pitchers normally used in relief, referred to as openers.^[1] This approach saw the Rays set MLB single season records for most no decisions by starters (91)^[2] and most wins by relievers (55).^[3] They finished the season with a 90–72 record, their first winning season since 2013; however, for the fifth consecutive year, they failed to make the postseason. This was because the Red Sox had 108 wins for the division title, while the Yankees had 100 wins and the Athletics had 97 wins for the wild card.

On December 11, 2017, the Rays acquired Joey Wendle in a trade in exchange for a player to be named later. One day later, the Rays traded minor leaguer Deion Tansel to the San Diego Padres for Ryan Schimpf.^[4]

On December 20, 2017, the Rays traded longtime franchise player Evan Longoria to the San Francisco Giants for Denard Span, Christian Arroyo, and two other prospects.^[5]

On February 21, 2018, the Rays were involved in a three team trade, trading Steven Souza Jr. to the Arizona Diamondbacks and receiving Anthony Banda and two players to be named later, from the Diamondbacks and Nick Solak from the New York Yankees.^[6] The next day, the Rays traded Corey Dickerson to the Pittsburgh Pirates for Daniel Hudson, minor leaguer Tristan Gray, and $1 million.^[7]