It comes after BMW revealed the 32-year-old would join its stable fresh out of Formula 1.
Magnussen bolsters a high-profile line-up, which also includes Philipp Eng, Robin Frijns, Raffaele Marciello, Rene Rast, Sheldon van der Linde, Dries Vanthoor, and Marco Wittmann.
Magnussen will be paired with Marciello and Vanthoor in the #15 entry while Frijns, Rast, and van der Linde pilot the #20.
The Danish driver will also contest three races in the IMSA SportsCar Championship – Daytona, Sebring, and Road Atlanta.
BMW has made sweeping changes to its IMSA line-up with Jesse Krohn and Connor De Phillippi both dropped for 2025. Nick Yelloly has also moved across to Acura.
Eng is the only BMW driver from its IMSA program who has remained year on year.
Eng will share the #24 with Vanthoor while the #25 will be shared by Wittmann and van der Linde. Magnussen and Frijns will join the #24 and #25 respectively for the longer endurance races.
Magnussen’s program will total 11 races, headlined by the 24 Hours of Le Mans.
“We have high goals for the upcoming season with our BMW M Hybrid V8 prototypes,” said Andreas Roos, head of BMW M Motorsport.
“To achieve these, we are striving for optimisations in all areas. For our driver line-up, this means focusing and specialising.
“The more time our drivers spend behind the wheel of the BMW M Hybrid V8, the better they will get to know its handling and the more feedback they can provide to our engineers.
“ The goal is to intensify the development of the BMW M Hybrid V8 in collaboration with the specialists at the teams and at BMW M Motorsport.
“It also helps us in this regard, that some drivers compete in both championships, thereby further improving the exchange of information.
“We are convinced that this way joining our forces will bring us advantages.”
A clash between the IMSA race at Laguna Seca and the WEC race at Spa-Francorchamps means the WEC line-ups will be slimmed down to Marciello/Magnussen and Frijns/Rast.
“Of course, the schedule overlap in May is not ideal, but we have the regulatory option to compete in a 6-hour FIA WEC race with two drivers per car, which we will utilise,” Roos said.
“The fact that the season starts in January with the 24-hour race at Daytona is very beneficial for us.
“This allows us to have all eight drivers together for an extended period early in the season, helping us to optimally synchronise with each other.”
2025 BMW M Motorsport driver line-up
WEC #15 – Kevin Magnussen/Rafaelle Marciello/Dries Vanthoor
WEC #20 – Robin Frijns/Rene Rast/Sheldon van der Linde
IMSA #24 – Phillip Eng/Dries Vanthoor + Kevin Magnussen/Rafaelle Marciello (Endurance Cup)
IMSA #25 – Maro Wittman/Sheldon van der Linde + Robin Frijns/Rene Rast (Endurance Cup)