EXPLAINED: Things to know about the latest rule changes for 2027

The FIA has formally approved a comprehensive package of sporting, technical and financial regulation changes for the FIA Formula One World Championship, marking the latest step in the governing body’s ongoing refinement of the 2026 rulebook.

The updates, endorsed by the World Motor Sport Council, reflect the collaborative approach that has defined the early phase of the new regulatory cycle — and signal the sport’s intention to balance innovation, sustainability, performance and safety as the next generation of Formula One machinery takes shape.

The FIA has confirmed a series of targeted sporting regulation changes for the 2027 Formula One season, refining several operational areas of the race weekend while addressing safety considerations and improving the balance of running time for teams and drivers.

The updates, approved as part of the governing body’s ongoing regulatory evolution, aim to streamline pre-season preparation and provide clearer, more flexible procedures for extreme weather conditions.

The most notable change concerns pre-season testing, which will expand from three to four days starting in 2027. The additional day removes the long‑standing need for teams to split at least one day of running between their two drivers, a compromise that often limited meaningful mileage and complicated testing programmes.

While teams may still choose to alternate drivers between morning and afternoon sessions, the new structure allows for a cleaner two‑day allocation per driver, increasing both development time and operational clarity.

The FIA has also updated the protocol surrounding extreme heat. A declaration of a ‘Heat Hazard’ — a measure introduced to protect drivers during dangerously high temperatures — can now be applied separately to the Sprint and the Grand Prix.

Under the revised rule, race control may declare a Heat Hazard for either session, or both, provided the decision is communicated at least 24 hours before the scheduled start time. The change gives organisers greater flexibility to respond to evolving conditions across the weekend.

Another significant update concerns power unit deployment in adverse weather. Boost mode, previously removed from wet‑weather running, has been reintroduced for conditions involving low grip or poor visibility.

However, its functionality will remain strictly limited: the system may be used only to prevent power reduction, not to increase overall output. The FIA emphasised that the adjustment is driven by safety considerations, ensuring consistent drivability without enabling performance gains in hazardous conditions.

The first issue of the 2027 Technical Regulations has been ratified, incorporating structural and wording improvements as well as targeted technical updates. These changes aim to enhance clarity, consistency and enforceability, while integrating lessons learned from the first season of the 2026 ruleset.

The FIA emphasises that this is part of a continuous process: as teams gather real‑world data from the new generation of cars, the governing body will adjust the framework to ensure competitive fairness and regulatory stability.

Formula One’s power unit landscape is set for a significant shift over the next two seasons, after the FIA formally approved a series of proposals that will steadily increase the contribution of the Internal Combustion Engine (ICE) relative to the electrical systems.

The changes, which will take effect in 2027 and 2028, are designed to refine the balance of performance within the hybrid power units introduced under the 2026 regulations, while addressing concerns raised by teams during the development phase.

Under the updated framework, the sport will move toward a 60/40 power split between the ICE and the MGU‑K by 2028, marking a clear recalibration of the hybrid philosophy. The shift will be achieved through a combination of increased combustion‑engine output and revised limits on electrical deployment.

By 2028, the ICE will produce 450 kW, representing a 50 kW increase over the current specification. In parallel, the maximum power from the MGU‑K will be reduced to 300 kW, though the overtake mode will remain capped at 350 kW. The electrical system’s harvesting capability will grow, with maximum regeneration rising from 350 kW to 400 kW, ensuring that energy recovery remains a central performance factor even as the combustion engine regains prominence.

To unlock the additional ICE performance, the FIA will implement a staged increase in fuel flow rate: a 5% rise in 2027, followed by a more substantial 13% increase in 2028. These adjustments had previously prompted concerns within the paddock, particularly regarding the potential need to shorten race distances to accommodate higher fuel consumption.

Teams also highlighted the financial implications of modifying chassis designs under the cost cap, especially as several had hoped to carry their 2026‑spec monocoques into 2027 to manage budgets. In such cases, simply fitting a larger fuel tank would not have been feasible.

FIA President H.E. Mohammed Ben Sulayem underlined the importance of continued cooperation between the FIA, Formula One, the teams and power unit manufacturers as the championship adapts to the most significant regulatory overhaul in a decade.

“As with every major regulatory change, the process does not end when the cars first take to the track. Continuous dialogue and collaboration are essential to ensuring that the regulations meet the needs of the sport, its drivers, and its fans,” he said.

Ben Sulayem also confirmed that discussions are already underway regarding future power unit concepts, including the possibility of V8 engines powered by fully sustainable fuels — a sign of the FIA’s willingness to explore multiple technological pathways for the sport’s long‑term future.