Seamus Conneely celebrated a last minute equaliser to make it two goals in two games for the midfielder.
Conneely fired home in injury time after Nicky Hunt's effort had been pushed out by keeper Will Norris, the ball bobbled around the area before the Irishman's shot found the back of the net from the underside of the crossbar.
It rescued a point for Stanley who had looked on course for a loss after Ryan Bird's deflected effort had given Cambridge the lead 11 minutes from time.
A long ball forward by Josh Coulson was missed by defender Rob Atkinson and Tom Elliott nipped in to head home beyond Scott Davies.Stanley's first chance didn't come until the 21st minute but Gerardo Bruna's long range effort was well off-target.
The Reds struggled to get into the game but, on 30 minutes, a swift move ended with Sean Maguire finding Josh Windass who forced a save out of debutant keeper Will Norris – although the off-side flag was already up.
However Piero Mingoia made his chance count six minutes before the break when Maguire got the ball and sent the wideman racing free and he expertly slotted past keeper Norris for his eighth goal of the season.
The Reds came close to taking the lead three minutes after the restart after Luke Joyce's ball opened up the Cambridge defence. Norris did well to deny Maguire and then Cambridge threw bodies in front of Windass's follow-up to keep the scores level.
And then it was Cambridge's turn to come close as sub Sullay Kaikai had only been on the pitch seconds when he was put clean through but his shot fizzed across the goal and narrowly wide.
There were a few goalmouth scrambles which the Reds had to deal with and Coleman put on Michael Liddle for the injured Adam Buxton, Shay McCartan for Windass and Kal Naismith for Bruna as second half progressed.
However it was Cambridge who again took the lead when Stanley didn't clear a long throw, it finally came to Ryan Bird whose strike took a deflection which left Davies with no chance.
But, as the fourth official held up five minutes of injury time, Conneely celebrated his second league goal and the equaliser.