Major League Rugby will add three teams and expand its regular season to 96 matches when it kicks off its third season in 2020.
The New England Free Jacks, Old Glory DC, in Washington DC, and Atlanta's Rugby ATL are set to join, bringing the total number of teams to 12.
The teams will be divided into two conferences next year - a Western Conference comprised of Austin, Houston, Glendale, San Diego, Seattle and Utah and an Eastern Conference featuring Atlanta, New England, Washington D.C., New Orleans, New York and Toronto.
The third season kicks off on 15 February, 2020 and will culminate with a final between the best team from each conference on 28 June, 2020.
The league has seen steady growth since its inaugural season last year, expanding from seven teams and 31 matches in season one to nine teams and 75 matches in season two, which is currently underway.
"Professional rugby is here to stay in North America," said MLR commissioner Dean Howes, who was previously chief executive of Major League Soccer's Real Salt Lake.
"MLR is the first time the North American sports model has been applied to the global game of rugby," he said.
"That model is now laying the foundations for the long-term success of this league and the sport. For everyone involved in MLR, from our team operators to our players, fans and media partners, our ultimate goal is to see North American rugby thrive."