Following the last Pirelli tyre test session at the Mexico City Grand Prix, the Italian tyre manufacturer has announced which tyre compounds will homologated on 15 December.

The current 2025 slick tyres range from the hardest C1 compound, to the softest C6 compound. Pirelli pick three of these compounds to bring to each circuit, and they make their decision depending on various factors like: track layout, asphalt abrasiveness and the weather forecast.

In 2026, however, they will only be selecting from C1 - C5, as the prototype for 2026's C6 tyre didn't see any obvious advantage over the prototype C5 tyre.

Pirelli shared: "Tyre development was carried out on the basis of forecast data as supplied by the teams, using simulations referring to loads and speeds predicted for the end of the 2026 season, while pursuing objectives similar to those of this year."

The new 2026 technical regulations has also made Pirelli's tyre testing slightly more arduous, with the introduction of active aerodynamics and slightly narrower tyres for next year adding some variables into the equation.

The Italian manufacturer continued: "The models were validated based on the results of development track testing with mule cars modified to reproduce the characteristics of the next generation of cars. That was a complicating factor during testing, stemming from the fact that tyres could not be tested on actual 2026 cars, which will run slightly narrower 18 inch tyres than the current ones."

The final day of 2026 tyre testing will take place on the 9 December, just a couple of days following the conclusion of the 2025 season. Teams will be supplied with the C2-C5 slick tyre compounds and in principle, the current drivers are expected to test the tyres, driving a mule car.

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