St. Louis will get the postseason event in 2018, and Tampa will have it in 2022.
The SEC tournament will be played in Nashville, Tennessee, in the nine other years between 2015 and 2025. The league made a long-term committee to Nashville last year, calling it the ''primary site'' for its men's tournament.
Missouri joined the SEC in 2013, opening up the possibility of playing events in St. Louis, a major television market.
Tampa previously hosted the SEC tournament in 2009 -- amid down years for basketball powers Florida and Kentucky -- and didn't fill the venue.
SEC commissioner Mike Slive says, ''We think that was an anomaly and we can get the kind of support that we want.''