EASA vs UK CAA Part-66: What Is Different in 2026

EASA Part-66 and UK Part-66 are two licensing systems that share a history and most of their wording, but no longer share the same exams. If you are studying for your modules, the difference decides how long each paper is, whether you write essays in Module 9 and 10, how many attempts you get and which authority's licence you end up holding. This guide sets out every difference that matters for the exams and the licence in 2026, and what stayed the same.

Part-66 Prep is an independent study aid, not EASA, the UK CAA or a Part-147 organisation. The rule texts are Regulation (EU) No 1321/2014 (Annex III is Part-66) for the EU and the retained UK Part-66 on legislation.gov.uk for the UK. Check both against your authority's pages before you book.

Why there are two Part-66 systems

Until the end of 2020 the UK was part of the EASA system, and the CAA issued EASA Part-66 licences like any other member state authority. When the Brexit transition period ended on 1 January 2021, EU aviation law was copied into UK law as "retained" regulation. The UK version of Regulation (EU) No 1321/2014, including Part-66, became UK law, and the CAA became the sole authority for UK licences.

Since then the two texts have drifted. The biggest change came with Commission Implementing Regulation (EU) 2023/989, which replaced the EU Part-66 syllabus (Appendix I) and examination standard (Appendix II) and applies from 12 June 2024. The UK did not adopt it, so UK exams still follow the earlier syllabus and standard. The EU has kept moving: Regulation (EU) 2025/111, applicable from 13 February 2026, added a B1.E subcategory for electric aeroplanes and a new Module 18 on electric power plants. In the UK, the CAA consulted in January 2026 (RMT 0201) on adopting the revised syllabus; it says the new statutory instrument will be made in 2027 and mostly come into force in 2029, with a four-year transition. Until then UK exams follow the current UK Appendix II.

Key fact: The rules that apply to your exam are the rules of the authority whose licence the exam counts towards: EU exams for an EASA licence, UK exams for a UK licence. Your Part-147 organisation can tell you which system its exams follow.

What is the same in both systems

Most of the examination standard did not change. These rules apply under both EASA and UK CAA rules:

Rule	EASA and UK CAA
Question format	Multiple choice, three options, one correct
Time allowed	About 75 seconds per question
Pass mark	75% for each module or sub-module
Negative marking	None
Essay time and marking	20 minutes per essay; pass with 75% of the key points and no significant error
Resit wait	90 days after a fail, or 30 days after a Part-147 retraining course tailored to the failed subjects
Part retake	If only the multiple-choice or only the essay part is failed, only that part is retaken
Validity of passes	Exams must be passed within 10 years before the licence application (66.A.25)
Cheating	A candidate proven to have cheated is barred from all exams for 12 months
Licence validity	The licence document is valid for 5 years and is then renewed (66.A.40)

The basic experience requirements in 66.A.30 also use the same durations in both texts, from one year after a Part-147 basic course for category A, B1.2 or B3 up to five years without relevant training for B1.1, B1.3 or B2. The experience requirements guide covers them in detail.

Exam differences: EASA vs UK CAA

Essays

This is the difference candidates notice first.

	EASA (from 12 June 2024)	UK CAA
Module 7	2 essays	2 essays (7A, or 7B for B3)
Module 9	No essay	1 essay (9A, or 9B for B3)
Module 10	No essay	1 essay

The CAA notes that an essay passed at category A level counts as a pass at category B level, so an engineer who passed the Module 10 essay for category A does not repeat it for B1. For how essays are marked and how to plan 20 minutes, read the Part-66 essay questions guide.

Attempt limits

	EASA	UK CAA
Limit	3 attempts per module in any 12-month period	3 consecutive attempts per module
After the limit	Wait until an attempt drops out of the 12-month window	A 1-year wait, then a new set of 3 attempts
Declaration	Written statement of attempts in the preceding 12 months	Written confirmation of attempts in the last year

In practice the EASA rule is a rolling window: three fails within 12 months stop you until the oldest one is more than 12 months old. The UK rule counts consecutive attempts and then imposes a fixed one-year pause. Both still need the 90-day gap after every fail. The resit rules guide has worked examples.

Partial exams

Under EASA rules, a module exam with more than 90 minutes allowed may be split into two partial exams, and one with more than 180 minutes into three. Each part has a number of questions that is a multiple of four, must be passed at 75% on its own and is taken at the same organisation. UK Part-66 has no general partial-exam rule; it only says the B2 Module 13 paper may be split into two examinations.

Paper sizes

Several papers have a different number of questions. Under both systems the time follows from 75 seconds a question. These are the main differences (questions per paper):

Module and category	EASA	UK CAA
1 Mathematics, B3	32	28
2 Physics, B3	32	28
4 Electronic fundamentals, B3	20	8
5 Digital techniques, A	20	16
5 Digital techniques, B1.2	40	20
6 Materials and hardware, B1	80	72
6 Materials and hardware, B3	80	60
7 Maintenance practices, A	76 + 2 essays	72 + 2 essays
7 Maintenance practices, B3	80 + 2 essays	60 + 2 essays (7B)
8 Basic aerodynamics, all	24	20
9 Human factors, A, B1, B2	28	20 + 1 essay
9 Human factors, B3	28	16 + 1 essay (9B)
10 Aviation legislation, B1, B2	44	40 + 1 essay
10 Aviation legislation, B3	44	32 + 1 essay
13 Aircraft systems, B2	188	180
14 Propulsion, B2	32	24
16 Piston engine, B1.2	76	72
16 Piston engine, B3	76	68
17 Propeller, B3	32	28 (17B)

Every other paper, including the long Module 11A, 12 and 15 papers, is the same size in both systems. The Part-66 modules guide lists every paper for every category.

What the difference adds up to

Added together across every module a category sits, the gap is modest for most categories and large for B3. These totals are multiple-choice questions only; essays are on top.

Category	EASA total	UK CAA total	Essays (EASA / UK)
B1.1	716 questions	692 questions	2 / 4
B1.2	660 questions	612 questions	2 / 4
B1.3	672 questions	648 questions	2 / 4
B2	684 questions	652 questions	2 / 4
B3	552 questions	448 questions	2 / 4

So a B1.1 candidate under UK rules answers about 24 fewer multiple-choice questions over the whole licence but writes two extra essays. The extra essays are in Modules 9 and 10, which most people sit early, so UK candidates meet essay writing sooner. EASA candidates meet it only in Module 7, usually one of the later modules, which is a reason to practise essay structure well before booking it.

Exam tip: On Part-66 Prep, choose EASA or UK CAA rules on a paper's start screen and the paper takes that size and time. Try it on Module 9 paper 1 or Module 10 paper 1, where the difference is largest.

Syllabus differences

Regulation (EU) 2023/989 also rewrote parts of the EU syllabus. The UK syllabus is the earlier version, so some topics now appear in only one system.

Module 7 Maintenance practices

The EASA Module 7 is a single module. It dropped sub-module 7.4 (avionic general test equipment) and 7.15 (welding, brazing, soldering and bonding), added additive manufacturing under material handling, and added a separate sub-module on documentation and communication. The UK keeps Module 7A and 7B with the older list. If you study from a pre-2024 textbook for an EASA exam, check the topic list against the current Appendix I.

Module 9 Human factors

The EASA Module 9 is a single module that now ends with safety management and the "Dirty Dozen" and risk mitigation. The UK keeps 9A and 9B, ending with hazards in the workplace. The core content, human performance, social psychology, the environment, communication and human error, is the same.

Module 10 Aviation legislation

This is where the content genuinely differs, because each system's legislation is now its own. EASA Module 10 covers the EU framework, EASA, Part-145, Part-CAO, Part-M, Part-ML, Part-CAMO and Part-21 and adds oversight principles and cybersecurity. UK Module 10 covers the same subjects under UK law, with the UK CAA as the authority. When you practise Module 10, use material for the system you are sitting. Our free Module 10 regulatory framework note explains the EU structure, and the Module 10 questions page explains how to prepare for either.

Modules 11 and 17

The EU merged 11A, 11B and 11C into one Module 11 with category columns, and 17A and 17B into one Module 17. The papers are still category-specific, so a B1.1 candidate sits the turbine aeroplane content in both systems. The difference is mainly in how the syllabus and certificates are labelled.

Licence differences: recognition and moving between systems

The exams are only part of the picture. The licences themselves are not interchangeable.

• An EASA licence does not give UK privileges, and a UK licence does not give EASA privileges. The UK and the EU treat each other as third countries for Part-66.
• You can hold both. Engineers who work for organisations in both systems often hold a UK licence and an EASA licence from an EU member state authority, each with its own renewal date.
• Moving between systems usually means applying to the other authority with your existing licence and certificates as evidence. The authority decides which modules or differences you must pass. Rules and transitional arrangements have changed since 2021, so read the current UK CAA engineer licensing pages and the EASA Part-66 FAQs, and ask the authority before you plan exams. The licence conversion guide explains the process.
• Licence fees are set by each authority. The CAA charges £455 for a UK AML application or renewal (CAA charges as checked in October 2026); EU authorities set their own fees. See Part-66 licence cost.

Which system should you study for?

Study for the system whose licence you need. That usually depends on where you will work:

1. Working in the UK on UK-registered aircraft: UK CAA rules and a UK licence.
2. Working for an EU operator or maintenance organisation: EASA rules and an EASA licence from an EU member state, often the country where you train or work.
3. Working for an organisation that holds both approvals: many people take one system first and add the other later.
4. Training with a Part-147 school: the school's approval decides which exams you sit. UK Part-147 schools run UK exams; EU Part-147 schools run EASA exams.

If you sit UK exams at a CAA venue, the CAA module exam booking guide explains the process and fees.

Your study plan

1. Decide which authority's licence you need and tell your exam centre or Part-147 school.
2. Take the free diagnostic for your category, for example the B1.1 diagnostic or the B2 diagnostic.
3. On every paper's start screen choose EASA or UK CAA rules, so your practice papers match the real length.
4. If you are on UK rules, practise essays for Modules 7, 9 and 10; if on EASA rules, Module 7 only.
5. Book each module when you score 85% on three different papers, and keep an eye on the attempt limits for your system.