Polling stations opened on Saturday in Iceland, where the leftist coalition elected in 2009 in the wake of the country's financial crisis is expected to be voted out of power.
The right-wing Independence Party and the centrist-agrarian Progressive Party, who both want to end the North Atlantic nation's EU accession talks, are expected to form a new coalition.
The biggest party traditionally picks the prime minister but polls in the final weeks of campaigning have put the two parties neck-and-neck.
What's clear is that the country will have a new leader after the vote, with social democratic Prime Minister Johanna Sigurdardottir, 70, having announced her retirement.
She leaves behind her a country that's economically healthier than it was four years ago, but an electorate struggling to cope with a combination of government austerity measures and a high level of household debt.
The two men battling to succeed her are the conservative Bjarni Benediktsson, 43, and his centrist counterpart Sigmundur David Gunnlaugsson, 38.
Benediktsson was expected to cast his ballot in Reykjavik on Saturday, while Gunlaugsson will be in the sparsely populated eastern part of the country, reflecting his party's more rural profile.
The 63-seat parliament, or Althing, is elected by proportional representation.
Polls opened at 9:00 am (0900 GMT) and will close at 22:00 (2200 GMT), when the first estimates of the outcome are expected. The final results will be announced early Sunday morning.