For the first time since the stadium was built in 1907, the 82,000-seater home of English rugby union will be rebranded as part of an agreement the RFU insists will be "transformative" for the game.
The first fixture to be played at Twickenham, which is sited in the southwest London district from which it takes its current name, under its new banner will be the women's international between England and New Zealand on September 14.
But unlike other sponsorship deals where the original name of the ground is retained -- for example cricket's Emirates Old Trafford in Manchester -- the fact 'Twickenham' will no longer appear in the new official title is sure to upset many rugby traditionalists.
The RFU have declined to reveal the amount being paid by Allianz for the naming rights, as well its investment into the senior England teams and community game, but insisted the sums involved were "significant".
"We're really pleased to be expanding our partnership with Allianz, enabling further investment into the community and professional game," RFU chief executive Bill Sweeney said.
"This is an opportunity to celebrate our stadium's proud legacy while developing it for the future."
"This partnership will support us in moving the game in a direction which serves all rugby, from minis to the elites, from club coaches to our national coaches and everything in between.
England are staging next year's women's World Cup, with the Red Roses and reigning champions New Zealand -- who beat them in a Covid-delayed 2022 final in Auckland -- thew two favourites for the title.
"As we head towards hosting the women's World Cup in 2025, it is entirely fitting that the first game to be played at the newly named Allianz Stadium will be the Red Roses versus New Zealand on 14 September," added Sweeney.
Allianz already sponsor seven other sports stadiums around the world, notably the Allianz Arena in their headquarters city of Munich.