The outcome gives Social Democratic leader Antti Rinne (pictured), a former finance minister, the task of finding coalition partners to form the first left-leaning government in two decades.
What are the results?
- The Social Democratic Party emerged with 17.7% support after campaigning against austerity imposed by the outgoing center-right government.
- The nationalist-populist Finns Party came second place at 17.5%.
- The conservative National Coalition Party, which is in the outgoing center-right governing coalition, garnered 17%.
- Prime Minister Juha Sipila's Center Party took 13.8%.
Climate and welfare policySocial Democrat leader Rinne said: "For the first time since 1999 we are the largest party in Finland ... SDP is the prime minister party."
"Let us, my friends, take the Finnish society toward sustainable climate, social and economic policies," he told supporters.
Prime Minister Juha Sipila offered congratulations to the opposition after his Center Party suffered heavily at the polls.
"The Center Party is the biggest loser in these elections. This result is a big disappointment for us. I want to congratulate the winners," he said.
Finns Party chairman Jussi Halla-aho, who received the most votes of any candidate, said he was surprised his party did so well. "I certainly could never have expected a result like this," Halla-aho said. "Honestly speaking, none of us expected this kind of result."
Likely numbers of seats200 seats were up for grabs in the Eduskunta parliament.
- The Social Democrats won 40, six more than in the 2015 elections.
- The Finns Party secured 39 seats. It won one additional seat compared to 2015, before a split that saw more than half of the party's lawmakers leave the parliamentary group.
- The National Coalition Party took 38 seats.
- The Center Party shed 18 seats to 31.
- The Greens and the Left Alliance won 20 and 16 seats, respectively.
- Two smaller parties, the Swedish People's Party of Finland and the Christian Democrats, won 9 and 5 seats, respectively.
- Voter turnout was 72 percent.
The EU is watchingFinland is set to take over the rotating EU presidency on July 1. European capitals were watching the performance of the Finns Party, which saw its support surge in the run-up to the vote. Many observers expect similar euroskeptic and nationalist parties make strong gains in next month's EU parliamentary elections. The Finns Party is part of a nationalist bloc of European parties aiming to challenge EU policies on migration, security, family and environment.
What were the dominant campaign issues?
Welfare:Sipila's outgoing center-right coalition had sought to implement a health care and social care reform plan, but failed to get it through the legislature. It also implemented unpopular welfare cuts in an attempt to reinvigorate the economy. Rinne advocated for increasing taxes and spending to preserve health and social benefits and a world-class education system. Read more: Finland keeps crown as world's happiest country
Immigration:Only 6.6% of the population is foreign-born, the lowest rate in Western Europe. Until recently, immigration was only a minor election issue. However, the Finns Party has attracted voters from small towns and villages worried about the issue, especially following highly publicized incidents of alleged sexual assaults by migrants last year. Other party leaders have cautioned against anti-immigrant rhetoric and generalizations about migrants. Rinne supports moderate work-related immigration and taking in some asylum-seekers. Read more: Climate protection - where do the EU's right-wing populists stand?
Climate change:Most parties support efforts to combat climate change, but they differed during the campaign on how far to go and at what cost. The Finns Party used the debate as a wedge issue to attract voters skeptical of the costs of further action.
What's next?The outcome means the Social Democrats will have to cobble together a coalition of three or four parties. The fragmented parliament and divisions between parties over welfare reform indicate that coalition talks could be drawn out. During the campaign, most parties voiced reservations about partnering with the Finns Party.
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cw,rc/se (dpa, AP, AFP)