Halifax had trailed 15-6 to the Yorkshire Two-based outfit but a superb fightback – including a 16th try of the season for Toby Turner – saw them clinch the honours.
Fax will now take West Leeds in the final on Saturday at Bluehill Lane (3pm ko). All support is welcome as the club look to finish the season with silverware.
Halifax will confirm their 19-man squad for the game in due course.
Address: West Leeds RUFC, The Clubhouse, Bluehill Lane, Leeds, LS12 4NZ