The league's commissioner, former South Africa captain Graeme Smith, said teams would be allowed to field a maximum of four foreign players per match when the competition gets underway next year.
It is to start on Jan. 23, as South Africa make a belated entry into the increasingly lucrative T20 market, and will run for a month.
The six franchises, based in Cape Town, Durban, Johannesburg, Paarl, Port Elizabeth and Pretoria, were all bought by owners from the Indian Premier League and Smith said they would be able to pick their teams from a "quality list" when a player auction is held on September 19th.
"We've got an extensive list of international players that we're sorting out for the auction. We're still finalising some of the auction details and we're sorting out the player registration because of the large number of players," Smith said.
"There has been an element of pre-signing that has been taking place and the teams have a purse of $2million that already includes the pre-signed players."
"A lot of work has gone into it and we're very excited with what we've done and what we can create going forward," he added.
England internationals Moeen Ali, Jos Buttler, Sam Curran and Liam Livingstone have already been signed along with West Indians Jason Holder and Kyle Mayers.
The start of SA20 clashes with the latter stages of Australia's Big Bash League, but Smith said agreements are in place for Big Bash League players who have signed for SA20 to leave and play in South Africa.
"They have a different structure this season, so the players in our league who have signed up will be there up until the early days of January so that they will be available," Smith told a virtual news conference.
"They'll be released to come and play here, from where they'll be fully available for the South African league."
