Sinn Féin will be the largest party in the Northern Ireland Assembly for the first time, pushing the Democratic Unionist Party (DUP) into second place.
Sinn Féin has 27 seats, compared to the DUP’s 25.
The result means Michelle O’Neill will be entitled to become first minister – unprecedented for a nationalist.
Earlier, Ms O’Neill said it had been an election of “real change” and a “defining moment for our politics and for our people”.
“Today ushers in a new era which I believe presents us all with an opportunity to reimagine relationships in this society on the basis of fairness, on the basis of equality and on the basis of social justice,” she continued.
“My commitment is to work through partnership, not division,” Ms O’Neill said after she was elected in Mid Ulster.
“We will work with those who serve all other political perspectives, we will show respect and we expect to be shown respect.”
A unionist party has had the most seats at Stormont since Northern Ireland was formed in 1921.
The cross-community Alliance Party has returned 17 MLAs, more than doubling its previous number in 2017.
The Ulster Unionist Party (UUP) lost one MLA to return with nine, while the SDLP’s seats fell from 12 to eight.
Counting in the Foyle constituency continued into a third day, with the DUP’s Gary Middleton the last assembly member elected in the early hours of Sunday.
Thirty-two of the MLAs elected are women, compared with 27 who were returned in the last election.
Northern Ireland Secretary Brandon Lewis said he would meet with the party leaders over the coming days with the aim of restoring the Stormont institutions “at the earliest possible moment”.
“I encourage the parties to form an executive as soon as possible. The people of Northern Ireland deserve a stable and accountable local government that delivers on the issues that matter most to them,” he said.
In February, the executive collapsed when DUP assembly member Paul Givan resigned as first minister.
As the first and deputy first minister roles are part of a joint office, the move also removed Michelle O’Neill from her position.
Taoiseach (Irish prime minister) Micheál Martin said a new power-sharing executive was “vital for progress and prosperity for all in Northern Ireland”.
“It is now incumbent on all political parties and elected representatives to deliver on their mandate, through the nomination of a first and deputy first minister and the formation of a new executive to serve the interests of all of the people of Northern Ireland.”
The US State Department called for the parties “to take the necessary steps to re-establish a power-sharing executive”.
“Critical and immediate challenges concerning the economy, health, and education are best addressed through the collective efforts of a devolved government chosen by, and accountable to, its people,” said Ned Price.
Although Sinn Féin can now nominate a first minister, they cannot take up the office unless the DUP, the biggest party from the unionist bloc, agrees to nominate a deputy first minister.
Its leader Sir Jeffrey Donaldson has not yet made a decision on whether the party will do that.
On Saturday, the DUP leader said his party would respect the result of the election, however, there needed to be changes made to the Northern Ireland Protocol.
The protocol is an element of the UK’s Brexit agreement with the European Union which keeps Northern Ireland aligned with the EU single market for goods.
Some unionists have said the protocol created a trade border between Northern Ireland and Great Britain.
BBC