Kuwait opposition groups and their allies have won nearly half parliament's 50 seats, raising fears of fresh political wrangling in the oil-rich Gulf state.
The opposition and its allies won 24 seats, according to official results announced by the election authority on Sunday.
Opposition groups contested Saturday's election after a four-year boycott protesting the government's amendment of the key voting system.
Around half of the successful opposition MPs are from a Muslim Brotherhood-linked group and Salafists.
A third of the new parliament are new, young members and the Muslim Shia minority was reduced to six seats from nine in the previous house.
Only one woman, Safa Al Hashem, was elected. Her win marks a return to politics for Al Hashem, who was previously elected in 2013 before resigning a year later. Fifteen other women stood for election.
Following the news, Al Hashem thanked her 328,000 Twitter followers "from the bottom of [her] heart" for giving her strength throughout the campaign.
"I remember those who raised the slogan 'for the sake of Kuwait'," she added, "from those who won and those who lost.
"I'm sure they have translated these slogans into actions to be reality on the ground."
The polls saw a turnout of around 70 percent.
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Saturday's snap elections, Kuwait's fourth since February 2012, were called by the Emir in October, after the government said "delicate regional circumstances and... security challenges" required a popular vote.
The move, however, was widely seen as linked to disputes between government and parliament over austerity measures including a sharp hike in state-subsidised petrol prices.
Kuwaiti voters dealt a heavy blow to members of the outgoing parliament, retaining only 40 percent of them.
A majority of those elected have openly said they will oppose any austerity measures by the government to boost non-oil income.
The government's overwhelming control in the previous assembly has been reduced to a fragile majority.
The reason behind the government's ability to hold on to a majority is the rule that sees unelected cabinet ministers also become members of parliament.
Their presence in the parliament helps to consolidate the grip of the Al-Sabah ruling family on the house.
Unlike other oil-rich Gulf Arab states, Kuwait has an elected parliament with powers to hold ministers to account, even though senior members of the ruling family hold all top cabinet posts.
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The set-up has led to repeated standoffs between politicians and the ruling family and Saturday's vote was the seventh general election in a decade.
But the strength of the opposition allows them to grill ministers and possibly even vote them out of office.
The election comes with Kuwait facing its most acute budget crisis in years. Oil income, which accounts for 95 percent of government revenues, has nosedived by 60 percent over the past two years.
The OPEC member posted its first budget deficit of $15bn last year following 16 years of surpluses.
Kuwaiti citizens make up around 30 percent of the emirate's population of 4.4m.
Source: Al Jazeera News and Agencies