The Conservatives have lost control of three councils, while Labour gained two in early local election results.
Labour candidate Chris Cooke also won the race to become mayor of Middlesbrough – taking the role from an independent incumbent.
Sir Keir Starmer’s party has taken Plymouth and Stoke-on-Trent from no overall control, and the Tories have lost Tamworth, Brentwood and North West Leicestershire to no overall control.
Labour is also performing best when it comes to seat gains – clocking up over 40 so far – compared to the Conservatives, which have lost more than 70.
But all eyes are on the next few hours, where more local authorities could change hands.
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Voters went to the polls on Thursday to decide who runs services in 230 (out of 317) local authorities across England, with around 8,000 councillors’ seats up for grabs.
Mayors are also being chosen in Bedford, Leicester and Mansfield in what is the biggest round of local elections since 2019.
It’s also the largest test of public opinion this side of the next general election, and Labour’s chance to capitalise on national polls suggesting it is on course to form the next government.
It is still early days at the counts, with only 39 councils having declared, but Labour has shown sound gains when it comes to both seats and vote share in numerous areas, including Thurrock, Rushmoor and Redditch.
The majority of those councils who have confirmed their results so far only had a third of their seats on the ballot, meaning few authorities have changed hands.
The coming hours will see more councils with all their seats up for grabs – like the areas that have seen major upsets so far – so a clearer idea of the parties’ performances are yet to emerge.
Tory MP Johnny Mercer, who represents Plymouth as an MP, called it "a terrible night" in his constituency as "we lost every seat we stood in".
He added: "Take it on the chin, learn and go again tomorrow. It’s going to be a fight but I like a fight."
Labour called its win in Middlesbrough "a huge result and beyond our expectations".
Meanwhile, the Liberal Democrats are also showing early seat gains – currently up by 18 – and the party is confident they have taken control of Windsor and Maidenhead, former Prime Minister Theresa May’s seat.
The Green Party is also currently up by 10 seats.
See full elections results as they come in
The seats on offer were last contested in 2019, when Mrs May was weeks away from resigning, and her party lost 1,300 seats.
Labour, led by Jeremy Corbyn at the time, also suffered losses with the Lib Dems, Greens and independents coming off best.
Sixty-two councils expect a result from midnight through to breakfast time.
More than half the 230 councils file their results in mid to late afternoon, while around 30 are expected to declare their results after teatime.
There are no local elections in Scotland or Wales, but voters in Northern Ireland will be able to have their say on 18 May, with 462 seats across 11 local councils up for grabs.
This set of local elections was also the first time voters had to bring ID with them in order to cast their ballot.
After voting ended, the Electoral Commission said "overall, the elections were well run", but it would begin a fuller analysis to discover the impact.
Its spokesperson said the ID requirement "posed a greater challenge for some groups in society" and "some people were regrettably unable to vote today as a result" of the change.
Labour also raised concerns about the new law, with shadow health secretary Wes Streeting telling Sky News: "One eligible voter turned away and disenfranchised is one too many."
But Tory minister Chris Heaton-Harris called the voter ID requirement a "thoroughly good thing" as it "means that you can be completely sure that your elections are well tested and safe".
Here are the benchmarks from Sky News’ elections analyst Professor Michael Thrasher for what would make a good and bad night for the main parties:
• Fewer than 300 losses: This would see the party winning council seats back from Independents, with Labour and the Lib Dems not prospering.
• 500 losses: The party could argue "mid-term blues" and will assume Labour could be caught before the general election.
• 750 losses: This would indicate a clear swing to Labour, but still less than opinion polls imply.
• 1,000 losses: A very bad night, with a third of all seats defended by the Conservatives lost.
• 700 gains: The best local elections for at least a decade. Labour would look on its way to becoming the largest party in Westminster, even if short of a majority.
• 450 gains: These results would be better than in 2022, when local elections took place in Greater London.
• 250 gains: A disappointing result for Labour in the context of recent opinion polls.
• Under 150 gains: A step backwards for Labour.
• 150+ gains: Eating into Conservative territory and could put some marginal constituencies in play at the next election.
• 50-100 gains: Comfortable enough in their own heartlands but only modest further progress.
• Fewer than 50 gains: Fewer than 50 gains: Still struggling to pose a real threat to the Conservatives in the south.
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