Rochdale missed the chance to go top of the National League as Josh Hmami fired Halifax to victory at the Crown Oil Arena.
Hmami gave the visitors the lead four minutes before half-time when he controlled Will Harris' header before finding the net.
The second goal arrived in the 54th minute when Angelo Cappello supplied Jamie John Cooke whose pass to the far post was nudged home by Hmami.
Devante Rodney hit back with a great 60th-minute finish against the club where he spent two loan spells.
But Rochdale's six-match winning run came to a crashing halt to leave them second, now two points behind Forest Green.
Match report supplied by PA Media.
