Part-66 Resit Rules: How Many Attempts and How Long to Wait

Part-66 resit rules decide how quickly you can try again after a fail, how many attempts you get and how long a pass lasts. They are the same in both systems in some places and different in others, and the attempt limit is the rule candidates misunderstand most. This guide sets out each rule, gives worked dates for both systems, and explains how to use the waiting time so the next attempt is the last.

Part-66 Prep is an independent study aid, not EASA, the UK CAA or a Part-147 organisation. The resit rules are in Appendix II to Part-66 and in 66.A.25 and 66.B.200: for the EU, see the EASA Easy Access Rules for Continuing Airworthiness and Regulation (EU) 2023/989, which set the current EU standard from 12 June 2024; for the UK, see UK Part-66 on legislation.gov.uk. For all the exam rules in one place, see the Part-66 exams hub.

Part-66 resit rules at a glance

Rule	EASA	UK CAA
Wait after a fail	90 days	90 days
Shorter wait	30 days after a Part-147 retraining course tailored to the failed subjects	Same
Attempt limit	3 attempts per module in any 12-month period	3 consecutive attempts per module
After the limit	Wait until an attempt leaves the 12-month window	1-year wait, then a new set of 3
Declaration	Written statement of attempts in the preceding 12 months	Written confirmation of attempts in the last year
Partial retake	Only the failed part (multiple choice or essay)	Same
Validity of a pass	10 years before the licence application (66.A.25(d))	Same, with a CAA extension in extenuating circumstances
Cheating	12-month ban from all exams	Same

The EASA vs UK CAA comparison explains why the attempt rules differ: the EU rewrote its exam standard in 2023, and the UK kept the earlier text.

The 90-day rule and the 30-day exception

After a failed module exam you may not resit it for 90 days from the date of the fail. The idea is that you need time to study the subjects you got wrong, not just book another attempt and hope for different questions.

The wait drops to 30 days if a Part-147 approved maintenance training organisation delivers a retraining course tailored to the failed subjects. The course has to be retraining by an approved organisation; reading notes on your own, or using a question bank, does not qualify. Ask your Part-147 organisation whether it runs retraining for the module, what it costs and what evidence it gives you for the exam centre.

Key fact: The 90 days run from the date of the failed exam, not from the date you received the result. Count from the exam date when you plan your next booking.

Results under review in the UK

If you ask the CAA for a full review of a result, the CAA advises not to resit or rebook until it has told you the outcome. If you resit anyway and the review upgrades your first result to a pass, the second result is voided. Reviews and fees are covered in the CAA exam booking guide.

Part-66 attempt limits with worked dates

The two systems count attempts differently, and the difference matters once you have failed twice.

EASA: three attempts in any 12 months

The EU rule is a rolling window. At any moment, look back 12 months: you may not have made more than three attempts at that module in that period. Worked example, using the shortest possible gaps:

1. You fail Module 3 on 12 January 2026.
2. The earliest resit is 12 April 2026 (90 days). You fail again.
3. The earliest third attempt is 11 July 2026. You fail again.
4. You now have three attempts within 12 months. Your next attempt must wait until the 12 January 2026 attempt falls outside the window, so from 13 January 2027 at the earliest.

If you had spaced the attempts out more, the window would open sooner after the third. Check with your exam centre exactly how it counts the 12 months, because the declaration you sign covers "the preceding 12 months".

UK CAA: three consecutive attempts, then one year

The UK rule counts consecutive attempts and then imposes a fixed pause:

1. You fail Module 3 on 12 January 2026, again on 12 April 2026, and again on 11 July 2026.
2. That is three consecutive attempts. You must wait one year before a new set of three.
3. Your next attempt is possible from about 11 July 2027.

A Part-147 college in the UK has published that the CAA confirmed to it that "3 consecutive attempts" means three failed attempts regardless of the time between them. That is a training organisation's report, not CAA wording, so confirm it with the CAA or your exam centre if it affects you.

Exam tip: Treat the second attempt as your last safe one. After two fails on a module, take the full 90 days, use tailored retraining if it is available, and do not book until you are scoring 85% or more on three different full papers.

Retaking only the failed part

If a module has both multiple-choice and essay parts and you fail only one of them, you retake only that part. Under EASA rules that applies only to Module 7. Under UK rules it applies to Module 7 (two essays), Module 9 (one essay) and Module 10 (one essay). The CAA also treats an essay passed at category A level as a pass at category B, so you do not repeat it when you add B1 or B2.

Under EASA rules, long papers may be split into partial exams (two for papers over 90 minutes, three over 180 minutes), each passed at 75% on its own. Ask your exam centre how it handles a failed partial exam before you sit, because practice varies.

How long Part-66 module passes last

The 10-year rule (66.A.25(d))

Module exams must have been passed within the 10 years before you apply for the licence or for the addition of a category. A pass from 2017 is still usable for an application made in 2026; a pass from 2015 is not, unless the credit rules in 66.A.25 allow it. Experience must fall within the same 10 years.

A worked example: you passed Module 1 in March 2018 and are still collecting the rest of your B1.1 modules alongside your experience. To use that Module 1 pass, your licence application must go in before March 2028. If your last module or your experience will not be ready by then, you either plan to resit Module 1 or, in the UK, consider an exam credit extension, described below. Keep a simple list of every pass with its date and the date it reaches 10 years.

Once your licence is issued, the passes recorded on it stay with the licence. The 10-year window matters for passes you are still collecting, so plan your sequence so the early modules do not expire before you apply. The EASA Part-66 FAQs restate the 10-year rule for exams and experience.

UK exam credit extension

The UK CAA may extend the 10-year period in extenuating circumstances, on application. As of October 2026, its AML examinations page states that:

• the fee is £183, paid with the "Application for an Exam Credit Extension" form on the CAA applications portal;
• only basic exams issued by a UK Part-147 organisation or by the CAA are eligible;
• no extension is granted if the syllabus has diverged between when you sat the exam and when you apply; you sit the module again instead;
• type training certificates cannot be extended;
• the CAA decides the length of any extension.

EASA states have no equivalent in the EU rule text; ask your national authority if a pass is close to 10 years old.

Resit situations candidates ask about

Changing exam centre

The attempt limit is per module and per candidate, not per exam centre. Moving from one Part-147 organisation to another, or from a Part-147 to the CAA, does not reset your count, and the written declaration you sign at the new centre must include attempts made elsewhere.

Sitting both the UK and EASA version of a module

Since 2021 the UK and EU exams are separate systems, and each authority's rules apply to its own exams. Some dual-approved Part-147 organisations let candidates sit both versions of a module. How an attempt in one system is treated by the other is not spelled out in either rule text, so declare every attempt honestly and ask the exam centre if you are unsure.

Failing at category A level and moving to B1

A category A paper and a B1 paper for the same module are different exams with different sizes, but they cover the same module. If you have recent fails at either level, ask your exam centre how they count towards the limit before you book the other.

The cost of a fail

A fail costs more than the exam fee:

Cost	Typical amount
CAA module exam resit	£60 per attempt (CAA, as of October 2026)
Part-147 resit or external candidate fee	set by each organisation; ask before booking
Tailored retraining for the 30-day route	set by each organisation
Time	at least 90 days, or 30 with retraining, before you can try again

The time cost is usually the biggest. A fail late in your experience period can delay a licence application by months, which is why booking only when you are consistently passing practice papers pays off.

Cheating and the 12-month ban

Under 66.B.200, a candidate proven to have cheated, or to have taken material relating to the exam subject into the exam, is barred from all basic examinations for 12 months, not just the module concerned. At CAA venues that includes written notes on paper or on your person and any electronic device. Read the venue rules before the day.

Using the waiting time well

A fail is information. The certificate or results page usually tells you only that you failed, so you need to find out what went wrong yourself:

1. Write down what you remember straight after the exam: topics that surprised you, questions you guessed. Do not try to reconstruct questions to share; exam content is confidential.
2. Diagnose by sub-module. Take the module's free quick practice and a full paper, then look at your score per sub-module. Most fails come from two or three weak sub-modules, not general weakness.
3. Drill the weak sub-modules. For example, if AC theory let you down in Module 3, the AC theory drill targets exactly that.
4. Re-sit full papers. Sit Module 3 paper 1 (or your module's equivalent) under timed conditions, then further papers. Our readiness rule is 85% or more on three different papers.
5. Book for the earliest sensible date, not the earliest legal date.

The study guides for each system set out the same rules in note form: EASA exam guide and UK CAA exam guide. If you are preparing without a course, the self-study guide shows how to structure your revision. The Part-66 Prep app also has an attempt tracker that records your exam dates and works out the earliest resit date for your system.

Pro on the pricing page unlocks papers 2 to 10 and sub-module drills for every module, which is useful when you need fresh papers after a fail. It comes with no pass guarantee.

What to do next

1. Check the date of your failed exam and count 90 days to find your earliest resit.
2. Count your attempts in the last 12 months (EASA) or consecutive attempts (UK) for that module.
3. Take the free B1.1 diagnostic or your module's free quick practice to find the weak sub-modules.
4. Sit a free paper 1 for the module, then drill the topics you missed.
5. Book through your Part-147 organisation or the CAA once you reach 85% on three different papers.