One Nation has picked up a fourth Senate seat as the final makeup of the upper house is decided.
The party's Warwick Stacey won the last of six Senate vacancies in NSW, the Australian Electoral Commission (AEC) announced on Friday.
He joins newly-elected Tyron Whitten, who won in sixth spot in Western Australia, re-elected Malcolm Roberts, who came in sixth in Queensland, and continuing senator and party leader Pauline Hanson.
The result means the party has the same number of senators as it did after the 2016 double-dissolution election — in which all seats in both the House of Representatives and Senate were up for grabs.
Hanson welcomed the result on Friday, saying her party had "defied the trend" of the federal election by winning seats in NSW and WA, and retaining Roberts' seat in Queensland.
"Our national vote increased significantly across Australia at this election thanks to a strong campaign with great candidates, common sense policies and dedicated volunteers," Hanson said.
"This team will continue the work we have always done in parliament on behalf of the Australian people: hold this toxic Labor government to account, raise the important issues, embody the strong conservative values that built this nation, defend our democracy, rights and freedoms, and put our country and its people first."
What are the Senate election results?
The AEC posted the results for NSW on Friday, confirming two Labor senators, two Liberal senators and one Greens senator, along with Stacey.
This followed results for Western Australia on Thursday, where there is a similar makeup of two Labor senators, two Liberal senators and one Greens senator, along with Whitten.
In Queensland, there will also be two LNP senators, two Labor senators, Roberts and the new leader of the Greens, Larissa Waters.
Earlier this week, David Pocock and Katy Gallagher were confirmed as ACT senators; three Labor candidates returned in Victoria, along with two Liberals and a Greens.
In Tasmania, the six returned are two Labor senators, two Liberal senators, one Greens, and Jacqui Lambie.
Labor's Malarndirri McCarthy and NT CLP's Jacinta Nampijinpa Price won in the Northern Territory, while three Labor senators returned in South Australia, along with two Liberals and a Greens.
Who controls the Senate?
This year's federal poll followed the 'regular' practice of half-Senate elections, in which half the 72 senators representing the states and the four senators representing the territories are elected. State senators serve six-year terms and territory senators three-year terms.
Labor will have 28 seats in the upper house, while the Coalition will have 27, and the Greens 11. One Nation will have four, with the remaining six going to independents or minor parties.
This means Labor will have to rely on the Greens or the Coalition to pass legislation.
