In the League One meeting between these two sides at Valley Parade a few weeks ago, it was Barnsley who turned in an impressive away performance and should have emerged with all three points, but it was role reversal this time around.
Bradford were the better side but spurned a string of excellent chances and needed an 82nd minute equaliser from former Manchester City full-back Richard Edghill to salvage a replay.
The main culprit in front of goal for the Bantams was veteran striker Dean Windass.
Normally so deadly, Windass squandered at least five decent chances inside the Barnsley box.
As for Barnsley, their main aim this season is to reach the League One play-offs but they are also keen to book an FA Cup third round place in the hope of drawing a big Premiership side.
Yet their display was well below par, with only Martin Devaney a likely source of inspiration on the left flank.
The home side badly missed the passing ability of Irishman Stephen McPhail and, as a result, it was the visitors who dominated the first half. Windass twice fired over the bar in the opening 15 minutes, while Danny Cadamarteri forced a fine tip-over save from Scott Flinders.
Bradford continued to press and Windass spurned three more close range opportunities before Barnsley snatched the lead against the run of play.
There was two minutes to go before the break when a deep cross from Aussie midfielder Jacob Burns was headed goalwards by captain Bobby Hassell and striker Paul Hayes was on hand to flick home his fifth goal of the season.
Barnsley were better after the break, but Burns was denied by a good save from Donovan Ricketts, while at the other end Windass finally found the net only to be ruled offside.
But eight minutes from time Bradford's 13th corner was only cleared to the edge of the box and Edghill's drive picked up a slight deflection which deceived Flinders and flashed into the net for a deserved leveller.