The new part-time professional top tier of Scottish domestic rugby will feature Ayr, Boroughmuir, Heriot’s, Melrose, Stirling County and Watsonians after they were awarded places in the competition following an application process in 2018.
Super 6 is due to start its season, contested over 12 rounds, on the weekend of 9 November 2019 and concludes with the final on 28 March 2020.
SRU chief executive Mark Dodson said when launching the Super 6 plan that he wanted a cross-border element and that has finally been firmed up on the day that WRU launched its new 12-team Indigo Group Premiership, with the Scottish/Welsh competition starting in mid-April 2020.
The confirmed teams from Wales are the top six placed teams from the last Welsh domestic club season - Merthyr, Cardiff, Pontypridd, Llandovery, E?bbw Vale and Aberavon.
The clubs will play six matches across two pools of six teams split between Scottish and Welsh sides.
An SRU statement said: “In year one of the competition every team will play three home and three away fixtures and the cross-border winner will be decided on a league ranking based on number of points gained over the six matches.
Scottish Rugby and the Welsh Rugby Union will now work together to finalise competition rules, commercial rights and confirm the broadcast opportunities.”
SRU chief executive Mark Dodson said: “This is another exciting step in the development of Super 6 and I’m delighted to join with the WRU and create a strong cross-border opportunity for our respective teams to compete in. We have developed a very positive working partnership with the WRU in recent years and this is an extension of that work.
“We want our Super 6 players to be exposed to a range of experiences which are designed to raise the standard of players at that level and we now know the Welsh teams they will pit themselves against and it promises to be a very interesting competition to see develop in the coming years.”
WRU group chief executive Martyn Phillips added: “We are thrilled that six of our Indigo Group Premiership teams will join Scottish Super 6 teams in a cross-border competition at the end of this season. It is an exciting development for our Premiership sides, while giving supporters something new to look forward to.”