The election result was on a knife edge on Saturday evening and, although Labor looked like winning the highest number of seats, it could be days before the final count is declared and it was not clear the ALP would secure a majority of 47 seats in the expanded 93 member Parliament, with a hung parliament and minority government in prospect.

In a disappointing night for the Liberal National Party and its leader Tim Nicholls - and one that could have significant federal implications for the Turnbull government too - the opposition saw big swings against it and votes bleed away to One Nation.

Ms Palaszczuk addressed her supporters at about 10.30pm in Queensland, and admitted "it was unlikely a result would be confirmed on Saturday evening". A high number of postal votes are still to be counted.

She stopped just short of claiming victory on the night, but declared "I remain confident we will be able to form a majority Labor government once all the votes are counted".

"I am overwhelmed by the support for Labor and I will continue to be a premier for all of Queensland. Based on tonight's results, our Labor members of Parliament will represent Queenslanders from the Torres Strait to the Gold Coast in the next Parliament," she said.

"I await the final days of counting with confidence and belief that a stable majority Labor government will be returned to work for all Queenslanders."

Mr Nicholls, however, said Queenslanders had voted to "shake things up" and while it was clear Ms Palaszczuk had not won a majority, "let's be realistic, nor have we".

"There are still over 360,000 postal votes to be counted over the coming days. Counting has now stopped and it will restart again at 9am tomorrow. Now, there are between 10 and 14 seats currently in doubt across Queensland and those seats will determine the ultimate outcome of this election," he said.

In a reference to his willingness to do a deal with minor parties, including One Nation, Mr Nicholls said he would "respect the will and the vote of the people of Queensland" but "the promise [from Ms Palaszczuk] was no deals with the Katters, no deal with the Greens, no deal with the minor parties and no deal with the independents. The question for Annastacia Palaszczuk is will she keep her word?"

With 69.2 per cent of the vote counted four-and-a-half hours after polls closed on Saturday evening, Labor was projected to secure a primary vote of 35.1 per cent, a drop of 2.4 per cent, while the LNP was projected to receive a primary of about 33.7 per cent, a fall of 7.6 per cent.

ABC election analyst Antony Green forecast Labor to secure at least 42 seats, the LNP 37 seats, Katter's Australia Party two seats, while 12 were in doubt.

He predicted there was "a high probability that Labor won't get to 47 [seats] and they're going to fall short, but there's no clear alternative government".

One Nation polled strongly, particularly in regional areas, with a projected primary vote of 13.8 per cent, but state party leader Steve Dickson lost the party's sole seat of Buderim and suggestions the party's haul of seats could reach double figures seemed wildly optimistic.

Former One Nation senator and self-proclaimed climate change expert Malcolm Roberts was smashed in his attempt to win the seat of Ipswich.

Mr Nicholls was hit by a 5.7 per cent swing and his seat is now marginal, while shadow treasurer Scott Emerson and shadow education minister Tracy Davis could both lose their seats.

On the Labor side, Agriculture Minister Leanne Donaldson looked set to lose her seat, but Deputy Premier Jackie Trad was expected to hang on despite a big swing to the Greens.

Labor's wins were mostly in and around Brisbane and the party lost a handful of seats in regional centres; the LNP strongholds of the Gold and Sunshine coasts largely held the line and the opposition outperformed the ALP in regional centres.

Federally, both Labor and the Coalition hold five marginal seats by less than 5 per cent, but Coalition MPs will be more nervous about the result.

Federal LNP MPs led by Barry O'Sullivan and George Christensen are planning to defy Prime Minster Malcolm Turnbull and cross the floor in Canberra to set up a banking commission of inquiry. And, after a night in which the LNP recorded big swings against it and One Nation claimed a double digit percentage of the vote, other Coalition MPs may be emboldened to follow suit.

Queensland is key swing state federally and both Mr Turnbull and Opposition Leader Bill Shorten visited the state during the campaign, though Mr Turnbull did not venture beyond Brisbane and Mr Shorten visited more frequently and travelled more widely.

Fairfax Media spoke to five Queensland federal Coalition MPs on Saturday before polls closed; they all predicted big swings to One Nation in the regions, and a narrow victory for Labor.

"If One Nation does well, it will be point proven that we [as a party] need a change of direction - it won't be good for Malcolm," was the pessimistic assessment of one MP before polls closed.

The warnings about the federal implications of a poor result for Mr Turnbull, who already faces increasing leadership chatter, will not go unnoticed.

Several factors, including the return of full preferential voting, the political divide between the populated south-east corner of the state - which favours Labor - and the regions - which leaned more towards the LNP and One Nation - made the result difficult to predict.

The south-east corner of Queensland, including Brisbane, Ipswich, and the Sunshine and Gold coasts, is home to 3.4 million people, while just 1.4 million people live in the vast expanses of the rest of the state.