Tallinn: Preliminary results from Estonia's parliamentary election show a centre-right party that held the prime minister's office for over a decade was the top vote-getter, but a far-right populist party also had a big win.

Returns reported early on Monday from all of the small Baltic country's 451 polling places gave the Reform Party 28.8 per cent of the vote from Sunday's election.

Prime Minister Juri Ratas' Centre Party, the senior partner in a coalition government, received 23 per cent. The nationalist Estonian Conservative People's Party, known as EKRE, had 17.8 per cent.

Reform Party leader Kaja Kallas arrives at a polling station during elections in Tallinn, Estonia, on Sunday. Credit:AP

Traditional power-brokers had hoped to prevent EKRE from gaining seats in parliament and vowed not to include it in a governing coalition.