Aidy Boothroyd’s men capitulated at the national stadium, conceding three times in 15 first-half minutes as they froze on the big occasion.
It was enough to give the Bantams the 3-0 win that secured a promotion to league one and consigns Northampton to another year in the basement division.
The league games between the two sides, which were both won by Bradford, were tight affairs but there was a clear chasm between them in this match.
Bradford looked as though they would score every time they went forward; the Cobblers didn’t have a notable shot on target for the entire match.
The three Bantams goals came in a 15-minute spell but this was a defeated that was deserved over the full 90.
There was no sign of the intensity, durability or organisational strength that were hallmarks of the semi-final victories over Cheltenham.
Instead they succumbed to Bradford’s shock and awe, allowing themselves to be trampled under the advance of the black and gold machine in a performance few would have predicted.
The first surprise of the afternoon came when the teams were confirmed, with Clive Platt and Ishmel Demontagnac - neither of whom had played in either leg of the semi-finals - in the Town starting 11.
Bradford went with their predicted line-up, both teams signalling their attacking intentions by playing 4-4-2 formations.
Northampton survived a few difficult moments in the game’s formative stages, with Nathan Cameron making an excellent hook tackle on Nahki Wells just as the forward shaped to volley a shot on the edge of the box.
But Bradford converted what was a narrow dominance into a scoreline advantage after a quarter of an hour.
A deep cross from their left reached Stephen Darby on the right, who chipped a cross back into the danger zone for Hanson to head over Lee Nicholls with a slight deflection off the top of Clarke Carlisle’s head.
The lead was doubled three minutes later in similar circumstances, a cross finding its way from the left to the right wing, where Nathan Doyle speared in a cross that Rory McArdle got across his marker to glance home at the front post.
The Cobblers mounted very little in the way of a response and it was Bradford who scored the game’s next goal, Wells peeling off his marker to tap home at the back post after Garry Thompson had headed Kyel Reid’s cross back across goal.
Reid then almost scored a fourth, arriving late at a throw-in and forcing Nicholls into a fingertip save with a firm header.
Town needed a route back into the game as swiftly as possible to give themselves any chance but it was Bradford who looked more likely to score throughout.
Carlisle hit a clearance against Hanson that was goalbound until Nicholls scampered across to push the ball wide for a corner.
Adebayo Akinfenwa’s introduction at least gave the home defence something new to worry about but he was unable to influence the game much.
He might have been had he started the game, or been introduced when his side were in a better position than three goals down.
The decision to leave him on the bench, and play a tired-looking Platt who looked visibly short of match practice in the 55 minutes he played, is one Boothroyd took with boldness.
But, with the benefit of hindsight, it was not the right one.
Cobblers: Nicholls, Tozer, Carlisle, Cameron, Collins, Hackett, Harding, Guttridge, Demontagnac, O’Donovan, Platt
Subs: Widdowson (for Collins 53), Akinfenwa (for Platt 55), Hornby (for Demontagnac 70)
Not used: Snedker, Johnson, Langmead, Robinson
Bradford: McLaughlin, Darby, Davies, McArdle, Meredith, Thompson, Doyle, Jones, Reid, Wells, Hanson
Subs: Atkinson (for Reid 78), Connell (for Wells 85), Ravenhill (for Doyle 87)
Not used: Duke, McHugh, Hines, Nelson