The visitors had fallen behind to a Bradford side which included three debutants and it was two of those players who combined to put City in front on eight minutes.
The Bantams made light of losing their star player Jermaine Johnson on transfer deadline day as fellow Jamaican Omar Daley created the opener.
His cross from the right picked out Billy Paynter - the striker on-loan from Championship strugglers Southend - who powered an effort towards goal only to see Paul Smith make a superb save.
But his fellow striker Bruce Dyer was on hand to mark his debut with a goal.
The lead did not last long, however, and just two minutes later Forest were level when Nathan Tyson side-footed home Wes Morgan's cross from an incisive breakaway.
Bradford were seeing plenty of the ball but the visitors always carried a goal threat with David Prutton pulling the strings in midfield.
And they got their noses in front on 18 minutes when Jack Lester cleverly turned David Wetherall in the box and slid his shot past Donovan Ricketts.
In the second half both sides had shots cleared off the line, but as the game wore on Forest sat deeper and deeper.
Each side had missed good chances when City boss Colin Todd brought on a third striker in a desperate bid for an equaliser and with just a minute left to play they found one.
Richard Edghill swung over a deep cross from the right which found the head of Dyer and, as the ball came down, Paynter was first to react and thundered in the equaliser.