The Six Nations will be completed in October and the Rugby Championship will run from November into December, World Rugby has announced.
The coronavirus pandemic saw the Six Nations men's and women's tournaments suspended in March – with four and six matches respectively still to be played.
England lead the men's table on 13 points, ahead of France, with each side in the competition having one game left to play apart from Ireland and Italy, who will face each other on October 24.
The final round of fixtures will take place on October 31, with Wales due to host Scotland, England set to travel to Italy and Ireland facing France.
The autumn internationals are expected to be replaced by an eight-team tournament, with Japan and Fiji reportedly joining the Six Nations sides.
In the southern hemisphere, the Rugby Championship – contested between South Africa, Australia, New Zealand and Argentina – will be played from November 7 to December 12.
The four-team tournament is set to be staged in New Zealand.
World Rugby chairman Sir Bill Beaumont said: "The global COVID-19 pandemic has been unprecedented in its impact on society and sport and throughout this process, all parties have sought to deliver the best-possible outcome to support the interests of international and club rugby and the players.
"These matches will be greatly anticipated by all, and I would like to thank unions, the international and club competitions and players for their input and the fans for their patience as we have sought to get international rugby back up and running."
Source – OPTA