EASA vs UK CAA Part-66: what actually differs

They started as one document. EU aviation safety law stopped applying to the UK on 1 January 2021. The text was kept as domestic law, changed to point at the CAA instead of EASA, and is now called assimilated direct legislation. At that moment the two were nearly identical.

They are not identical now, and only one side moved: EASA amended Part-66 twice and the UK adopted neither amendment.

So the UK text is frozen at its 31 December 2020 state, and legislation.gov.uk shows no later amendments to it. The CAA consulted in January 2026 on amending its own Annex III (RMT.0201). If that goes ahead, the UK figures on this page will move, which is why everything here is dated.

The most visible result is the numbering. Regulation (EU) 2023/989 abolished the A and B module suffixes from 12 June 2024, so EASA has plain Modules 1 to 18 and separates categories by column instead. The UK still has 22 module tables, including 7A/7B, 9A/9B, 11A/11B/11C and 17A/17B, and no Module 18. Two titles differ too: EASA’s Module 4 is “Electronics Fundamentals” against the UK’s “Electronic Fundamentals”, and EASA’s Module 11 dropped the word “Turbine”.

Four: Modules 6, 8, 9, 10. The other nine are identical for B1.1. Two of the four differ only in count, and two carry a UK essay that EASA removed in 2024.

The totals are worth reading carefully, because they do not move in the direction people expect. The UK sets 24 fewer questions than EASA and still takes 10 minutes longer overall. The essays account for it: EASA removed the Module 9 and Module 10 essays in 2024, leaving 2 essays and 40 minutes, while the UK still sets 4 and 80 minutes.

Everything else about the examination is common to both: three answers per question, a 75% pass mark, no penalty marking, and 75 seconds per question. The exam format page covers all of it, including the resit and attempt rules, which do differ.

This is the section that matters most and the one the headline hides. Four papers differ in question count. Nine modules differ in content. A candidate revising the wrong regime’s syllabus is studying the wrong topics, and nothing about the exam entry tells them so.

Two of those deserve singling out. In Module 10 the UK list is not a shortened EASA list, because it is renumbered from 10.4 onward, so the same number means a different topic in each regime, and EASA’s 10.4 “Independent certifying staff”, the only level 3 in that module, has no UK counterpart at any number. In Module 15, topic 15.15 is “Power augmentation systems” under the UK CAA and “Alternate turbine constructions” under EASA. Same number, different subject.

The knowledge level definitions themselves are one place the two genuinely agree: levels 1, 2 and 3 are word for word the same in both texts, and the UK made no EU Exit change to them.

No, in both directions, and there is no longer a route between them.

EASA on a UK licence: “An AML issued by a country other than EASA Member States cannot be rendered valid as EASA Part-66 AML.” An AML is an aircraft maintenance licence. A first EASA application must go to the competent authority of a member state, as a new applicant.

The UK on an EASA licence: recognition ended on 1 January 2023, after a two year transition. “From 1 January 2023, the UK can no longer recognise EASA-issued certificates, approvals or licences for the operations and/or maintenance of UK registered aircraft.”

The UK’s transfer route for EU Part-66 licence holders closed on 31 December 2022. One narrow route survives: if the UK issued you a licence within the last five years, and you transferred it to an EU member state before exit, you can apply for a replica to be reactivated with the same expiry date and ratings.

What remains in both directions is examination credit, and the authority decides each case. You may apply to the competent authority for full or partial credits for other technical training and exams the authority considers equivalent, backed by an approved examination credit report. “May apply” is the phrase doing the work.

The Trade and Cooperation Agreement between the UK and the EU does not help. It lists personnel licensing and training among the areas the parties may cooperate in, but what that part covers is set by annexes, and the only annex adopted covers airworthiness and environmental certification. The agreement also says plainly that nothing in it requires either side to accept the other’s standards.

It follows from the register of the aircraft you plan to certify, not from where you live. An EASA Part-66 licence is not accepted for certifying aircraft on the UK register, and a UK licence is not recognised in the EU system. Each licence has to come through its own regime.

Because there is no recognition and no conversion, holding both means qualifying twice, through each regime’s own route. Nothing stops you. Nothing makes it cheap either.

For study, the practical advice is simpler than the legal position: decide which authority’s paper you are sitting before you start revising, and check the topic list for that authority, not the one that comes up first in a search. Nine of the thirteen modules differ in some way, and two of them will silently teach you the wrong material.

This page answers one part of the B1.1 route in full. The rest of the guide covers the others.