Labor says it has won the 47th seat it needs to form a majority in parliament, but is yet to officially claim government.
The party on Tuesday night tweeted that Meaghan Scanlon had snatched the Gold Coast seat of Gaven from sitting Liberal National Party member Sid Cramp.
However, Labor has yet to claim victory overall and LNP leader Tim Nicholls has not conceded defeat, meaning both sides may wait until the Electoral Commission of Queensland formally declares a result.
Counting of votes is expected to pick up on Wednesday now that the postal vote deadline has passed.
Nearly 90 per cent of the state-wide first preference vote has now been counted, and the ECQ hopes to have a final result by the end of the week.
Preferences will also start to be distributed more fully, as candidates with the fewest votes are ruled out of contention and their preferences distributed.
More than 30 seats had been formally declared late on Tuesday – 17 for Labor, 13 for the LNP and one for Katter’s Australia Party.