The former Arsenal trainee grabbed the equaliser 14 minutes from time as the Shots made it seven draws from their last eight games.
Wycombe had looked set for a come-from-behind win after Danny Foster and Kevin Betsy cancelled out Luke Guttridge's early strike but Halls had other ideas.
Having gone close early on Guttridge opened the scoring in the 26th minute with a sensational 30-yard free-kick leaving Wycombe keeper Nikki Bull no chance.
But the home side got themselves level right on the stroke of half-time when Foster got on the end of a Betsy cross to convert from close range.
Betsy turned from provider to goalscorer after the break when he shot low past Shots keeper Jamie Young from 10 yards out. But the home fans' celebrations were ended when Halls popped up to give the Shots the last laugh and secure their 14th draw of the season.
Source: PA
Source: PA