What is ADUO? The FIA lifeline that could save F1 teams

Leclerc during FP1 at Suzuka — Photo: © IMAGO

F1 Explained

What is ADUO? The FIA lifeline that could save F1 teams

All you need to know about ADUO

Sheona Mountford F1 Journalist

Motorsport journalist working in F1 since 2024.

Saturday 28 March 2026 16:01

How d'ya ADUO? Welcome to our explainer on the latest acronym working the F1 commentary circuit, ADUO or Additional Development and Upgrade Opportunities.

The 2026 regulations have blasted and scattered the F1 field, with times at the top now representing a gulf compared to those at the bottom. At the Chinese Grand Prix alone the gap between pole position and P10 was well over one a second, with Mercedes possessing a healthy advantage at the front.

But don't resign yourself to a George Russell title victory (yet). For the FIA has a trick up their sleeve to help struggling power unit manufacturers. Whether it's Honda looking to lift themselves from P20 misery or Ferrari and Lewis Hamilton taking the title fight to Mercedes, teams may be given additional development time.

So, what is ADUO? How does it work, who gets it and when?

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Additional Development and Upgrade Opportunities (ADUO) Explained

The five power unit manufacturers on the grid are comprised of Mercedes, Ferrari, Red Bull Powertrains, Audi and Honda, who, on March 1 submitted their power unit designs to the FIA for homologation.

After this date, it is pretty difficult for power unit manufacturers to make any changes to their engine without seeking approval from the FIA. However, for those power unit manufacturers struggling to catch up with the rest of the field, a safety net was put in place.

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To receive this safety net - ADUO - power unit manufacturers must meet a specific criteria. According to Article 4 of Appendix 4 of the new technical regulations, a manufacturer qualifies for the upgrades if their: "ICE (Internal Combustion Engine) Performance Index is at least two per cent but less than four per cent below the best-performing ICE."

They are then eligible for one additional homologation upgrade in the qualifying year (i.e. 2026) and one additional homologation upgrade in the following season.

If their ICE Performance Index is 'at least four per cent below the best-performing ICE', a power unit manufacturer can then receive two additional homologation upgrades in the qualifying year and two additional homologation upgrades in the following year.

However, ADUO can only be bestowed at specific points in the year. So, when the calendar was made up of 24 races, this could be used every six races and Miami would be the first.

Following the cancellation of the Bahrain and Saudi Arabian Grands Prix, Miami will be the fourth round and would mean the next ADUO point would not be until the Monaco GP in June.

However, the FIA have reportedly submitted a proposal to have the date brought forward, so that ADUO can still be rolled out after the race in Miami.

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How could ADUO benefit Ferrari?

Ferrari team principal Fred Vasseur believes his team could be granted ADUO, even though Hamilton was only three tenths of a second behind Kimi Antonelli in qualifying at the Chinese GP.

Because ADUO is related to the ICE Performance Index, and not the chassis, Vasseur believes it is the Ferrari power unit that is lacking in comparison to Mercedes'.

He named ADUO as an opportunity for Ferrari to 'close the gap' on Mercedes, as he does not believe the compression ratio changes, that will arrive June 1, will put the Silver Arrows at too much of a disadvantage.

Mercedes' main advantage during the opening rounds of 2026 has been their power and top speed, with Ferrari needing more power on the straights to truly contest their rivals.

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