A new regional women's T20 tournament has been confirmed by the ECB for the summer of 2021, alongside the return of the 50-over Rachel Heyhoe Flint Trophy.
The increase in fixtures comes after the ECB awarded 41 full-time domestic contracts at the end of last year, in addition to the 17 centrally contracted England Women players.
The Rachel Heyhoe Flint Trophy will be played in two blocks, commencing on May 29 and with the final on September 25. Southern Vipers, who won the inaugural competition, will begin their defence against Lightning at the Ageas Bowl, with fixtures on the opening weekend also being played at Headingley, Chelmsford and Bristol.
The middle of the summer will be taken up with the Women's Regional T20, starting on June 26 and again placed in two blocks. The eight teams will be split into two groups, playing each other home and away; Finals Day will be held on September 5, with the best-placed group winner going straight into the final, and the other group winner and best-placed runner-up contesting the semi-final.
Northern Diamonds will take on Lightning at Headingley in a local derby to kick off the opening round of the WRT20, with fixtures also staged at Trent Bridge, Edgbaston and Taunton.
The return of a domestic women's T20 tournament comes after the successful Kia Super League was scrapped in 2019 to make way for the Hundred. The first three rounds of fixtures will be staged in June and July before a six-week break for the Hundred, after which teams will play the final three rounds and Finals Day.
"This promises to be a truly memorable summer of cricket for the women's game," Clare Conner, the ECB's managing director of women's cricket, said. "We are not only set to further professionalise the game with more players on full-time contracts than ever before but, crucially, we will showcase our game to more young girls across England and Wales so that they can say cricket is a game for them.
"I am particularly proud that we will continue to move forward with Rachael Heyhoe Flint's name, with everything she represented for women's cricket, firmly entrenched in our journey.
"The launch of women's regional cricket last summer, despite the challenges caused by the pandemic, was another significant step forward for our domestic game. We are now looking forward to seeing those regional teams play twice as much cricket this summer with the addition of the T20 competition."
England Women are scheduled to play two international series this summer, with fixtures - as well as those for the Hundred - still to be confirmed.
Women's Regional T20Group A: Southern Vipers, Central Sparks, South East Stars, Lightning
Group B: Northern Diamonds, Western Storm, Sunrisers, Thunder