Ashton-Langford signed with Connecticut in the fall, but reopened his recruitment in late March.
Providence was one of Ashton-Langford's finalists the first time around, and Ed Cooley's program was able to get Ashton-Langford on campus for a visit this past weekend.
"His relationship with Ed Cooley and the opportunity to impact a Big East program right [was] too much for Makai to pass on," Mass Rivals coach Vin Pastore said.
Ashton-Langford, a 6-foot-2 point guard who played this past season at Brewster Academy (New Hampshire), is ranked No. 36 in the ESPN 100 for the class of 2017. He joins a Friars recruiting class that also includes four-star center Nate Watson and three-star center Dajour Dickens.
Ashton-Langford helped lead Mass Rivals to an undefeated July last summer, averaging 13.0 points and 3.8 assists on the Adidas Uprising circuit.