The format has been agreed by the Rugby Football Union, Premiership Rugby and Rugby Players’ Association, building on the framework agreed during a meeting of global stakeholders in San Francisco last year.
The Gallagher Premiership, which has traditionally run from early September to the end of May, will now start and finish later.
Twickenham will host the finals on June 20, 26 and 18 for the years 2020-22 with the campaigns launching on October 20, September 12 and September 18 respectively.
England’s summer tours will take place in July rather than June to leave August as the only month clear of rugby either being played on these shores or by Eddie Jones’s men overseas.
England internationals will play a maximum of 30 full games per season, reduced from 32, and be confined to a limit of 35 match involvements of 20 minutes or more.
Players will have guaranteed in-season breaks under the new structure. RFU chief executive Stephen Brown said the new structure had focused “on the requirements of player welfare”.
Premiership Rugby chief executive Mark McCafferty said the structure achieved “a number of progressive goals for the English structure over the next three seasons, building in new player management approaches, reducing overlaps and scheduling more of Gallagher Premiership Rugby for the better weather conditions of spring and early summer”.
Wales head coach Warren Gatland has returned to New Zealand following the death of his father.