Gallagher Premiership champions Northampton will kick off the new domestic campaign against Bath in a repeat of last season’s Twickenham final.
Bath have also been confirmed as Bristol’s opponents for the first Premiership game to be played at Cardiff’s Principality Stadium on May 10 next year.
Northampton won their first Premiership title for 10 years when they beat Bath 25-21 in June.
Scrum-half Alex Mitchell’s try seven minutes from time saw Saints home, with Bath playing almost an hour of the final with 14 players after prop Beno Obano was sent off.
Northampton will head to the Recreation Ground for the opening night on Friday September 20, when Newcastle are also in action against Kingston Park visitors Bristol.
Saracens begin life without departed England trio Owen Farrell, Billy and Mako Vunipola with a trip to Gloucester on September 21, when Exeter entertain Leicester, while Harlequins head to Sale Sharks on September 22.
Saracens will return to the Tottenham Hotspur Stadium for a fourth successive season when they host Harlequins in March, with Quins staging games at Twickenham against Leicester in December and Gloucester five months later.
The first of two derby weekends takes place on October 11-13 with Newcastle facing Sale, Exeter hosting Bristol, Bath visiting Gloucester, Leicester entertaining Northampton and Saracens travelling to Quins.
Return fixtures are in March as the Premiership stages two rounds of derbies for the first time.
Every Premiership match will be broadcast live by TNT Sports and discovery+ for the first time, with the final on June 14 at Twickenham.
The final has been brought forward a week as part of a deal announced late last year between the Premiership and British and Irish Lions.
It means that Premiership players involved with the Lions’ tour to Australia will be able to take a full part in early stages of preparation for the visit Down Under.
In 2017 and 2021, there were clashes between the English league’s domestic showpiece and initial Lions training camps.
When the Lions faced 2021 warm-up opponents Japan in Edinburgh it took place on the same day as the Premiership final.
The 2025 Lions opening fixture is against Argentina in Dublin on June 20 before heading to Australia, where a three-Test trip begins in Perth eight days later when they tackle Western Force.
Premiership Rugby’s chief growth officer Rob Calder said: “After the enormous success of the inaugural derby weekend last season we are thrilled to add a second derby round for supporters to see those ferocious grudge matches.
“Marquee fixtures continue to excite new and existing fans and I know our partners are excited about showcasing these, too.
“So we are excited that Bristol Bears will be adding another huge occasion to the fixture list with the Big Day Out against historic rivals Bath as Premiership Rugby crosses the Severn Bridge.”