The 19-year-old’s deal expires at the end of the season and had interest from a number of English Championship clubs as well as Celtic.
Hastie is set to agree a pre-contract and sign a four-year deal as Steven Gerrard puts plans in place for next season with Jordan Jones also joining once his Kilmarnock deal finishes.
Motherwell were hopeful that their teenage star would follow David Turnbull, James Scott and Barry Maguire in committing their futures to the club.
However, Hastie has opted for a move to Rangers with the Steelmen due a development fee since the player has been in the academy since 2009.
The player’s rise has been rapid, exploding onto the scene with a double in a 3-0 win for Motherwell over Livingston in February.
That brace was followed by blockbuster strikes against St Mirren and Hearts, helping his side to three points on both occasions. He also netted in a defeat to Ross County in the Scottish Cup.
Hastie, who is 20 later this month, made his debut for the club in October 2016 and has had two spells out on loan, first with Airdrie and then Alloa Athletic in the first half of this campaign.