Richard Marshall’s side were leading 20-6 with only two minutes left to play.
But Ethan Ryan and Ted Chapelhow touched down for the Bulls in the final seconds, Oscar Thomas converting both, with the visitors’ desperate last throw of the dice only ending when Fax full-back Will Sharp mopped up a loose pass on his own 40 metre line on the final play of the day.
Josh Wood opened the scoring, slipping Sharp into half a gap then looping round to take the full-back’s offload and stepping past a couple of defenders to score.
Ben Heaton added a second, and Steve Tyrer converted both, plyus a penalty, to put Halifax 14-0 up.
The second half was a scrappier affair from the start and, eventually, it was Bradford who came up with some points, hooker Vila Halafihi slipping out of Sharp’s grasp to score by the posts in the 55th minute, Thomas’s conversion making it 14-6.
Thomas just did enough to force Jake Bibby onto the sideline as the Halifax winger went for the corner.
But they gave themselves a cushion soon after, prop Daniel Murray charging over and Tyrer kicking his 2,000th career point to put Fax 20-6 up.
That was how it stayed until the final two minutes.
Halifax: Sharp; Bibby, Tyrer, Heaton, Worrincy; Murrell, Wood; Cahalane, Moore, Murray, Grady, Barber, Grix. Substitutes: Morris, Walne, Boyle, Kaye
Bradford Bulls: Thomas; Chamberlain, Mendeika, Gibson, Ryan; Keyes, Butterworth; Oledzki, Hallas, Magrin, Bentley, Smith, Roche. Substitutes: Peltier, Kirk, Chapelhow, Halafihi
Referee: N Bennett (RFL).