The National Coalition Party topped the poll and the SDP and Greens lost big chunks of support compared to 2017, as turnout dipped in Finland's delayed, Covid-affected municipal election.
NCP leader Petteri Orpo revelled in his party's victory.
"Thank you to the Finnish people. Thank you to the voters. The NCP is the biggest party for the fourth time in a row," Orpo told cheering staff at the party's HQ.
The Social Democrats, meanwhile, had a bad night. Although she personally took more votes than any other candidate in the country during advance voting, SDP leader and Prime Minister Sanna Marin's party did not match her success.
"If the results stay the same it will of course be a disappointment," Marin said on Yle's election broadcast after learning of the voting projections. "Our candidates have worked really hard. We will of course analyse the results."
The Finns Party gained support, votes and councillors across the country, but they remained in fourth place — failing to dislodge the Centre Party as they had hoped.
The party is now the largest group on at least six councils, in Hamina, Orimattila, Kihniö, Ylöjärvi, Kankaanpää and Hämeenkyrö, and nationally is set to have more than 500 additional council seats than after the 2017 election.
In Helsinki the keenly-contested mayoral election was in the end not close at all. Green League candidate Anni Sinnemäki was hampered by a scandal over zoning decisions that broke two days before the election, and in the end the National Coalition was clearly the largest party in the capital.
According to the agreement between the major parties, that means the NCP candidate Juhana Vartiainen now becomes mayor of the capital.
In Tampere, the mayoralty went to the NCP after a nailbiting count which saw MP and former city mayor Anna-Kaisa Ikonen oust SDP incumbent Lauri Lyly by just 26 votes.
Turnout nationwide was down this time round, at 55.1 percent compared to 58.9 percent in 2017. That can partly be attributed to a lack of in-person campaigning in an exceptional, Covid-influenced election.
"Social media has played a bigger role than ever before," analyst Pekka Isotalus said on Yle's election broadcast. "New social media platforms like Instagram or Jodel were used throughout this election. The conversations (between candidates and voters) have been more interactive thanks to social media, and there has also been more campaigning against certain parties in social media"
Below is our live blog of the evening's events:
22:41 Yle projection: NCP biggest party, Finns Party biggest gains
With 86 percent of votes counted, Yle's projection suggests the National Coalition Party will be the most popular party in this election while the Finns Party will claim the biggest gains.
The projection also suggests a drop in support for the governing coalition partners the Social Democratic Party and the Green Party.
SDP chair and Prime Minister Sanna Marin was less than pleased with the numbers.
"If the results stay the same it will of course be a disappointment," Marin said. "We will of course analyse the results."
22:23 NCP vice chair Valtonen topping poll in Helsinki
With nearly half of all votes counted in Helsinki, the National Coalition Party (NCP) has a clear lead with 27.9 percent of the vote, well ahead of second place the Green Party on 21.2 percent.
NCP vice chair Elina Valtonen (formerly Elina Lepomäki) looks to be one of the big vote magnets, with 8,117 votes according to the count just after 10pm, and she would be on course for the position of Helsinki mayor if she had not already said she didn't want the job.
"I do not regret it at all. I believe that my place is in parliamentary and european politics," Valtonen told Yle.
She looked to be taking a swipe at her party's conservative wing in declaring the capital open to immigration.
"Helsinki wants to welcome all returnees (Finns moving back to Finland) and all people coming from within or outside the country's borders. Welcome to Helsinki!"
21:58 Turnout down on 2017
Turnout in the election was just over 55 percent, according to figures released by the Ministry of Justice.
That represents a drop of almost four percentage points from the turnout at the last local election in 2017, when 58.9 percent of eligible voters cast a ballot.
The elections have been affected by the pandemic, with campaigning restricted to online events in large part and much less of the normal market square activity.
21:10 Finns Party eyes gains
The Finns Party has been a big question mark in this election. The polls suggested big gains were likely for the party, as the 2017 election saw them finish on just 8.8 percent of the vote.
But getting their voters to turn out has always been a problem for the Finns Party, especially in local elections.
Party leader Jussi Halla-aho has already claimed victory, saying that the result is already the best in the party's history, but the numbers could change as the evening progresses.
"We know that the Finns Party is the party that suffers the most if voting activity stays low," said Halla-aho. "Historically we struggle the most in receiving the same support in local elections as we do in parliamentary elections."
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20:33 NCP leading in the capital
With 29 percent of the vote counted in Helsinki, the National Coalition Party (NCP) is on course to remain the capital's top party, and with increased electorate support.
"Helsinki will develop into a more sustainable, beautiful and bigger city," said the party's candidate for mayor, Juhana Vartiainen, on Yle's election broadcast.
The Green candidate for mayor, Anni Sinnemäki, told Yle's election night broadcast that news of a police investigation into her role in a zoning dispute may have affected the election.
"It for sure affected election day," said Sinnemäki. "However I have received a lot of positive feedback throughout this election."
The NCP currently stands on 29.6 percent of the vote, an 1.2 percent increase from 2017, and well ahead of nearest challengers the Green Party, who are currently on 21.7 percent.
The Finns Party, which had been projected to make big gains in the city, currently sits on 7.2 percent, which is an increase of just 0.4 percent from last time out.
20:25 Question marks remain
Normally in a Finnish election, all the advance votes have been counted by this stage of the evening. This time round the counting has been slower than usual, especially in the big cities.
The only conclusion we can draw from that with any great certainty is that the Centre Party's percentage will fall, as their power base is not in the big cities.
That means every party is still saying it is too early to draw conclusions. We'll keep you up to date with the results as they come in.
20:05 NCP leads after initial results
The initial results are in. These include votes from many, but not all, of the 32.9 percent of eligible voters who cast their ballots in advance.
Officials have been counting votes on Sunday, but some 400,000 votes remain uncounted because of the sheer volume of advance votes cast in this election.
Some 1.47 million votes were cast in advance this time, an increase of around 300,000 on the total from the last municipal election in 2017.
The greatest number of uncounted advance votes is in Uusimaa.
With those caveats out of the way, we can say that with 39.1 percent of the votes counted so far there has been an increase in support for the Finns Party, who have 13.5 percent of the total votes counted so far (up 4.2 percent on the results in 2017).
The National Coalition is top at this stage with 21 percent of the vote, followed by the SDP on 18.4 percent, then the Centre Party on 17 percent.
The count will be updated in the fact box in this blog and in real time at Yle's results service.
18:15 Polls close in less than two hours
There's just under two hours of voting left in Finland's local elections, so if you haven't voted yet there's still time. Results will start to filter through from 8pm, with advance votes already being counted.
Those advance votes account for some 32.9 percent of eligible voters, so we should have an indication of how things will go fairly early in the evening.
There are lots of stories to follow over the course of the evening. Here are a few of the results we'll be looking out for.
The Centre Party currently has more than 50 percent of the councillors in 80 councils, but they're under pressure from the Finns Party in much of their heartland. How many places will still be ruled by the Centre tomorrow?
The Greens were the biggest party in Jyväskylä in 2017, after finishing fifth in 2012. Will they keep their spot or fall back again?
The Helsinki mayoral race was rocked by internal wrangling in the National Coalition Party and a last-minute scandal involving Green candidate Anni Sinnemäki. Will she become mayor or will Juhana Vartiainen keep the post for the NCP?
There are also mayoral contests in Tampere and Turku, with the NCP hoping to take each of them.
15:40 Helsinki warns of results delay
Juha Viertola of Helsinki's central election committee told Yle that the tallying of advance votes may not be completed by 8pm owing to the large number—205,000—of early ballots cast in the capital.
"In 2017, Helsinki residents cast 125,000 votes in advance and 201,000 on election day. The situation has turned around this time," he explained.
The All Points North podcast has extensively covered this municipal election campaign, including interviews in English with each of the leaders of the main political parties. This week's episode looked into the polarisation of political opinion that has been a feature of the campaign, and also informed listeners what to look out for as results start to come in from around the country on election night.
13:05 Outdoor voting for those in quarantine
To accommodate voters in quarantine, election officials have organised outdoor voting at polling stations.
Janne Poutiainen, chair of the voting centre at Helsinki's City Hall, said a special feature of this election was that people in quarantine could also cast their ballot.
"People under quarantine can vote outside. This means we have to have more poll workers since people can cast ballots outside as well as inside," Poutiainen explained.
12:30 Tabulation of early votes begins
The tallying of votes cast during the advance voting period (from 26 May to 8 June) began at Helsinki's Finlandia Hall around noon, where 185 vote counters were ready to start opening envelopes.
Rules say municipal central election committees can start processing votes after noon.
Nearly 1.5 million people cast early votes ahead of Sunday's official election day. That represents some 33 percent of all those entitled to vote, up from 26.6 percent in the previous local election in 2017.
The counting of election day ballots begins at 8pm when polling stations close. Preliminary results are generally ready around 11pm.
Yle TV1 will begin its election night coverage starting at 7.30pm.
12:15 Officials urge election hygiene
Election officials are recommending that voters wear face masks or visors when arriving at polling stations. Poll workers may, however, ask voters to remove masks when confirming their identity.
12:00: Finland heads to the polls
Voting centres have been open since 9am. If you are heading to the polls on Sunday, be sure to check out out our really simple guide to the election.
For a quick refresher on what parties and candidates stand for in these elections, head on over to our English-language election compass to get your bearings.
The Ministry of Justice, which oversees elections in Finland, will begin releasing preliminary results from 8pm, when polling stations close.