The W17 is the first Mercedes car developed under the 2026 regulations, marking a shift from the hybrid era. Overseen by James Allison, the car is lighter, smaller, and narrower than its predecessor. A controversy arose during its development regarding a loophole in the new regulations, which Mercedes and Red Bull Powertrains exploited to achieve a higher compression ratio than the stated 1:16, based on measurements taken at ambient temperatures. The W17 completed its initial 200-kilometer shakedown at Silverstone, with both Russell and Antonelli testing the car.
The car's livery, unveiled on January 22, 2026, is similar to the W16, but with the removal of silver and the addition of Microsoft as the airbox sponsor. A zebra stripe pattern of silver and black, forming the AMG logo, has been incorporated along the sidepods.
The Mercedes W17 made its competitive debut at the 2026 Australian Grand Prix. George Russell topped the third practice session, while Kimi Antonelli crashed his car during the same session. Mechanics were able to rebuild Antonelli's car by the end of Q1, aided by a red flag caused by Max Verstappen's crash. In qualifying, Russell and Antonelli locked out the front row, with Russell finishing 0.785 seconds ahead of the closest non-Mercedes car.
In the Australian Grand Prix race, Russell initially lost the lead to Charles Leclerc's Ferrari, and Antonelli dropped to seventh. Leclerc and Russell traded positions for the first 12 laps, while Antonelli moved up to fourth behind Lewis Hamilton. Mercedes capitalized on a Virtual Safety Car on lap 13 to pit both cars. The leading Ferraris pitted later under normal racing conditions and emerged behind both Mercedes. Both W17s completed 45 laps on hard tires to secure a 1-2 finish, twelve seconds clear of the next car. This marked Mercedes' 61st 1–2 finish and their first since the 2024 Las Vegas Grand Prix, which Russell won. The result gave Mercedes an early lead in both championships.
At the Chinese Grand Prix, the W17 continued its strong performance. Russell took sprint pole ahead of Antonelli, securing another front-row lockout for the sprint race, which Russell won while Antonelli finished fifth. In qualifying for the main race, Antonelli became the youngest ever Formula One polesitter at 19 years and 6 months. Russell qualified second despite a Q3 issue that limited him to a single flying lap. In the race, both Antonelli and Russell initially lost positions to Ferrari but recovered. Antonelli secured his first Grand Prix win, becoming the second youngest ever Grand Prix winner behind Max Verstappen. He also set the fastest lap, becoming the youngest driver to achieve a hat trick of pole position, race win, and fastest lap. Russell finished second, marking back-to-back 1-2 finishes for the team.
The team maintained its dominance at the Japanese Grand Prix, where the W17 featured a special front wing design. Antonelli and Russell again locked out the front row. Despite dropping down the field at the start after being passed by Oscar Piastri, Antonelli used a well-timed safety car to retake the lead, which he held to win the race, also setting the fastest lap. Russell finished outside the podium for the first time that season, held off by Leclerc.