Rob Harker snatched a stoppage-time equaliser for Halifax, who missed the chance to move back into the play-off places after drawing 1-1 at home to York.
It looked like the Minstermen were going to make it four straight wins and pull six points clear of relegation danger after Dipo Akinyemi struck from close range in the 74th minute.
But poor goalkeeping from George Sykes-Kenworthy allowed Harker to score a simple tap-in in stoppage time.
Halifax are now two points off seventh-placed Aldershot but have games in hand on the teams above them, while York are four points off the drop zone.
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