The nods came after weeks of talks held following the 27 January resignation of PM Marjan Šarec, who had formed a minority centre-left government in September 2018.
The draft coalition agreement was initialled by the four parties on Monday, while consultation talks were held today with President Borut Pahor, who is likely to nominate Janša for his third stint as prime minister on Wednesday.
The parties, which have 48 votes in the 90-member National Assembly, have already divided the ministerial posts among them.
Several media reported that SMC head Zdravko Počivalšek would stay economy minister and DeSUS leader Aleksandra Pivec would remain in charge of the Agriculture Ministry, while NSi head Matej Tonin would become defence minister.
Other names circulated include the SDS's Anže Logar as foreign minister, the SDS's Zvonko Černač as interior minister, the SDS's Andrej Šircelj as finance minister, DeSUS's Tomaž Gantar as health minister, the SMC's Igor Zorčič as justice minister, the NSi's Cveto Uršič as labour, family and social affairs minister, and the NSi's Jernej Vrtovec as infrastructure minister. The SDS will allegedly also head the culture ministry.
Tonin indicated after the NSi's executive council session that the party had expected a little more from the coalition agreement, in particular bolder steps in healthcare.
56 of the NSi's 88 executive council members cast their vote today, all voting in favour.
Tonin confirmed the NSi had gotten the three departments mentioned by the media and that he would be put forward for defence minister. The candidates for the two remaining NSi cabinet posts are on the other hand still being discussed.
The second party to reveal its decision was the SMC, where Jani Möderndorfer, one of the SMC 10 MPs, was the only to vote against.
RTV Slovenija reported that some of the SMC's MPs allegedly received an offer from Marjan Šarec's LMŠ to vote against today and instead join the LMŠ to get favourable treatment on the party's slates in the next general elections.
SMC head Počivalšek told the press after the vote that "Slovenia needs an operational and mature government, capable of facing the challenges ahead".
"It is important to say that this will not be a coalition of one party… of one [party] president, this will be a coalition of four parties operating in consensus.
"This will also be a government for which 47% of voters voted in the last election and I am confident that such a government will work for the good of all of us," said Počivalšek.
Pivec of DeSUS revealed her party's decision shortly after, saying DeSUS was content with what it secured in the coalition negotiations.
Along with the agriculture and health minister, DeSUS is also expected to head the planned government demographic office. The vote on the executive council was 12:1 and on the council 45:5.
Addressing the press on behalf of the SDS was the party's MP Anže Logar, who explained that 219 of 219 SDS executive council members had voted in favour today.
He hopes the decisions adopted today will also be reflected in the parliamentary votes on the PM nominee and the ministerial team, which he hopes will proceed promptly.