The casinos were sold for $51m.
Twin River also gained sports betting licenses in Colorado.
Colorado is expected to launch sports wagering this spring.
The three casinos are conglomerated in a half mile strip and total nearly 20 table games and 700 slots.
Twin River already owns two casinos in Rhode Island, one in Mississippi and another in Delaware.
The company also runs the Arapahoe Park racetrack in Aurora, Colorado.
Twin River CEO George Papanier said: “Completing the acquisition of these three properties expands our footprint in Colorado well beyond our Arapahoe Park racetrack and Off Track Betting network. We are very pleased to close on this transaction, the latest in our ongoing efforts to diversify our portfolio.”
Papanier said that Twin River will soon announce partnerships with two sports betting franchises prior to the launch of sports wagering in Colorado.
In July, Twin River announced it would purchase the Isle of Capri Casino in Kansas City, Missouri and Lady Luck Casino Vicksburg in Vicksburg, Mississippi from Eldorado Resorts.
The deal was worth $230m.