Additional Development and Upgrade Opportunities (ADUO) is a mechanism within the 2026 Formula 1 Technical Regulations (Article C4) allowing Power Unit manufacturers whose Internal Combustion Engine (ICE) performance falls at least 2% below the best-performing ICE across defined review periods to introduce additional homologated upgrades to their Power Unit during the current and following season, but also to benefit from additional Cost Cap and dyno testing allowances. The level of ADUO is calculated over three periods in each season, with the level of allowance determined by the size of the performance gap to the leading ICE. The first review period was concluded after the Canadian Grand Prix, the second review period concluded after the Hungarian Grand Prix and the third review period concluded after the United States Grand Prix. 

The FIA can confirm that the results of the third ADUO analysis period of 2026 (Races 12 to 18) have been communicated to all Power Unit manufacturers. 

For the third period, the relative performance gaps to the leading ICE evolved, but these changes did not result in any additional homologations being granted to the Power Unit Manufacturers. 

Due to the confidential nature of this information, no further details on Power Unit performance index measurements will be communicated. 

As a reminder, the following results were communicated for period 1 of 2026: 

• Mercedes were determined to be in the 2-4% window, and are thus allowed 1 additional homologation in 2026 and an additional 1 in 2027, together with corresponding cost cap and dyno testing increases. 

• Audi, Ferrari and Honda were determined to be above 4%, and are thus allowed 2 additional homologations in 2026 and 2 in 2027, together with corresponding cost cap and dyno testing increases. 

For period 2, no additional homologations were granted to any Power Unit Manufacturers. 

Nikolas Tombazis, FIA Director of Single Seater, said: “The FIA has undertaken extensive analysis as part of the review of ADUO this year. Based on the quality of the data and the robustness of the assessment process, we are confident in our findings and the conclusions reached."

The first year of implementation has also reinforced our belief that the ADUO concept is the right one for Formula 1. However, it is important that the system continues to evolve to ensure it remains efficient, relevant and fit for purpose. To that end, we have been working closely with the Power Unit Manufacturers and teams to explore refinements to the methodology that will support the continued effectiveness of ADUO in future seasons." 

The next ADUO review period will start in 2027 and will cover races 1 to 6 (Bahrain to Miami). 

ENDS 

Note to editors: More information about ADUO can be found here. 

The Fédération Internationale de l'Automobile (FIA) is the governing body for world motor sport and the federation for mobility organisations globally. It is a non-profit organisation committed to driving innovation and championing safety, sustainability and equality across motor sport and mobility. 

Founded in 1904, with offices in Paris, London and Geneva, the FIA brings together 246 Member Organisations across five continents, representing millions of road users, motor sport professionals and volunteers. It develops and enforces regulations for motor sport, including six FIA World Championships, to ensure worldwide competitions are safe and fair for all.