ICAO English Levels: what Level 4, 5 and 6 mean.
Every EASA pilot who uses the radio telephone needs a language proficiency endorsement on their licence under FCL.055. The endorsement records which language was assessed, the level demonstrated, and when it must be re-evaluated. This guide explains what Levels 4, 5 and 6 actually mean, how the assessment works, what the re-evaluation intervals are, and how to prepare.
This page is general educational information only. Language proficiency rules, their national administration and approved testing bodies vary by competent authority and can change. Always confirm current requirements with your ATO and national aviation authority. SkyStudy is an independent study aid, not affiliated with ICAO, EASA, or any language testing body.
4 years
Minimum for the FCL.055 endorsement. Re-evaluated every 4 years under EU rules (national variation applies).
6 years
Re-evaluated every 6 years under FCL.055(c). Longer interval reflects stronger demonstrated proficiency.
No renewal
No re-evaluation required under FCL.055(c). The highest rating on the ICAO scale.
Re-evaluation intervals are set by FCL.055(c). National competent authorities administer the process and may apply different arrangements. Always verify current rules with your authority or ATO. SkyStudy is an independent study aid, not affiliated with EASA or any civil aviation authority.
Free practice tool
Train the six rated skills with SkyStudy's free ICAO English practice simulator.
Vocabulary, grammar, listening comprehension on radio recordings, timed speaking exercises, and a self-assessed mock test. Practice at your own pace, no sign-up required.
Practice simulator only. It cannot award an ICAO level or a licence endorsement; only an assessor certified by a competent authority or an approved language testing body can do that.
What each level means
The ICAO scale runs from Level 1 (pre-elementary) to Level 6 (expert). Levels 1 to 3 all fall below the licensing requirement, so the practical focus for pilots is understanding what separates Level 3 from Level 4, and what extra range earns a 5 or a 6. The table below shows Levels 3 to 6:
| Level | Name | What it means in practice | Licence effect |
|---|---|---|---|
| 6 | Expert | Speech is natural and effortless. Vocabulary is wide, precise and idiomatic. Grammar is consistently well controlled. Understands almost everything, including subtle meaning, and handles any turn in the conversation with ease. | No re-evaluation required. |
| 5 | Extended | Speaks at length with relative ease on familiar and work-related topics. Basic grammar is consistently solid; complex forms are attempted with occasional errors. Paraphrases reliably and is rarely misunderstood. | Re-evaluated every 6 years. |
| 4 | Operational | The minimum for the endorsement. Communicates effectively on common and work-related topics. Errors occur, especially in unusual situations, but rarely block the message. Can deal with an unexpected turn of events, even if it takes clarification. | Re-evaluated every 4 years. |
| 3 | Pre-operational | Below the licensing requirement. Handles predictable, familiar exchanges, but errors frequently interfere with meaning, hesitation often blocks communication, and unexpected situations cause real difficulty. | Not sufficient for the FCL.055 endorsement. |
Paraphrased in our own words from the rating scale in AMC2 FCL.055 and ICAO Doc 9835. The authoritative wording is the rating scale in those cited sources.
The six rated skills
Assessors do not give you one overall impression mark. They rate six separate skills, each defined in the AMC to FCL.055 and in the ICAO rating scale. Your overall level is the lowest of the six ratings, not the average. That matters for how you prepare: five skills at Level 5 with pronunciation at Level 3 gives an overall Level 3.
Pronunciation
Whether your accent, stress, rhythm and intonation interfere with being understood. An accent is acceptable at every level; an accent that blocks comprehension is not.
Structure
Your control of grammar and sentence patterns, from basic forms (past tenses, questions) up to complex ones (conditionals, reported speech), and whether errors change the intended meaning.
Vocabulary
The range and precision of the words you use on common and work-related topics, and your ability to paraphrase clearly when a specific term does not come to you.
Fluency
Your speaking pace, your control of hesitation, and your ability to produce extended stretches of speech rather than only short phrases. Assessors also listen for rehearsed versus spontaneous production.
Comprehension
How accurately you understand speech on routine topics and when a situation takes an unexpected turn, and how you cope with different accents and speech rates.
Interactions
How you manage the conversational exchange: timely, informative responses, and checking, confirming or clarifying effectively when something is unclear.
How ICAO English proficiency testing works
How ICAO English proficiency testing works
A live spoken assessment
ICAO English proficiency is assessed in a live spoken format, not a written grammar exam. The assessment is conducted by an assessor certified by a competent authority, or by an approved language testing body. There is no single worldwide exam. Each national competent authority approves its own assessors and testing bodies, and pilots typically contact their authority or ATO to identify which options are available to them.
The broad shape of the assessment is consistent across providers. Most include a listening element based on recorded aviation communications, a speaking interaction with the assessor about aviation topics and unexpected situations, and often a picture description task or a radiotelephony-style scenario. The focus throughout is on whether you can communicate clearly and safely in both standard phraseology and plain language.
What determines your level
The assessor rates each of the six skills separately. Your overall level is the lowest of those six ratings. This means a strong performance in five skills cannot compensate for a weak one: the weakest link determines the result. The design reflects the reality of radio communication, which fails at its weakest point.
For Level 4, the minimum, the standard requires that errors, accent and hesitation do not block effective communication. That explicit acceptance of imperfection is why focused practice on the specific rated skills pays off faster than general English study. You are not trying to sound like a native speaker; you are trying to communicate safely and clearly.
Common assessment formats
Several well-known assessment products exist. Examples include the TEA (Test of English for Aviation, administered by Mayflower College in the UK), ELPAC (developed by EUROCONTROL for aeronautical communication), and RELTA (from RMIT University in Australia). Many states also run or approve their own assessments, and some allow the demonstration during a skill test or proficiency check with a suitably qualified examiner.
Validity periods and renewal
Validity periods and renewal
FCL.055(c) re-evaluation intervals
FCL.055(c) sets how long a demonstrated level lasts before it must be re-evaluated. The stronger your result, the longer the interval:
- Level 4 (Operational): Re-evaluated every 4 years
- Level 5 (Extended): Re-evaluated every 6 years
- Level 6 (Expert): No re-evaluation required
National variation
The EU intervals above come from FCL.055(c) in the Aircrew Regulation. The exact administrative procedure (who signs the endorsement, how early you can re-test, which testing bodies are approved in your country) belongs to your national competent authority. Some states implement shorter validity periods or different requirements for specific pilot categories.
The endorsement on your licence records the language, the level, and the validity date. Letting it lapse removes your ability to exercise radio privileges under FCL.055 until the renewal is complete. Most pilots treat the renewal date like any other currency check: a calendar commitment protected well in advance.
ICAO English vs aptitude verbal tests: what is the difference?
ICAO English vs aptitude verbal tests: what is the difference?
These two types of assessment are often confused because both involve English language, but they measure different things and are used at different stages of a pilot career.
ICAO English proficiency (FCL.055)
Measures operational language ability: can you communicate clearly and safely on the radio, in both standard phraseology and plain language when something unexpected happens? The assessment is a live spoken interaction with a trained human evaluator. It applies to any pilot who uses a radio telephone, and the result is an endorsement on your licence. Preparation focuses on the six rated skills, especially on identifying and improving your weakest one, since overall level equals the lowest skill rating.
Aptitude verbal screening
Measures cognitive verbal reasoning ability under time pressure, typically as part of airline cadet or direct-entry selection. Common formats include reading short passages and answering True/False/Cannot-Say questions within tight time limits, and choosing word analogies or completing sentences at speed. These tests assess reasoning with language, not operational communication. Preparing for them will not improve your FCL.055 endorsement level, and improving your ICAO endorsement level will not improve aptitude verbal scores.
The aptitude verbal exercises on SkyStudy (verbal reasoning and aviation English) target the timed reasoning format used in selection. The ICAO English practice simulator trains the six proficiency skills for the FCL.055 endorsement. Both serve real pilot preparation goals; they are simply separate goals.
Practical preparation guidance
Practical preparation guidance
Start with your weakest skill
Because your overall level is the lowest of the six skill ratings, the fastest way to raise it is to work on your weakest skill, not your strongest. Be honest about where your gaps are. Ten hours on your weakest skill can raise your endorsement level; ten more hours on a skill already at Level 5 cannot.
Practise producing speech, not reciting it
The fluency descriptor explicitly distinguishes rehearsed from spontaneous speech, and assessors steer conversations to unexpected topics precisely to hear you think in English. Practise creating new sentences about aviation topics rather than memorising prepared answers. A useful habit is narrating a flight out loud for two minutes: what happened, what you did, how it ended. That single exercise trains structure, fluency and vocabulary at the same time.
Train the repair tools until they are automatic
Interactions are rated on how you detect and resolve misunderstandings. The standard aviation tools for this are: say again, confirm, correction, I say again, stand by. Knowing these phrases is not enough; they need to come out automatically before the message gets garbled. The ATC communications simulator trains exactly the readback loop where these repair phrases matter.
Train listening wider than phraseology
Comprehension is rated on plain language too, across different accents. Supplement structured listening exercises with live ATC streams, aviation podcasts and incident documentaries. The radio comprehension exercise trains the timed listening accuracy format. After every wrong answer in any listening drill, replay the clip while reading the transcript and find the exact word you missed; it is usually one word, not the whole sentence.
SkyStudy's free ICAO English practice simulator covers all six rated skills: vocabulary, grammar structure, listening on radio and plain-English recordings, timed speaking exercises with model answers, and a self-assessed mock test. It is a practice tool only and cannot issue an ICAO level or a licence endorsement. Use it to identify your weak skills, then bring those skills to a certified assessor.
Open the practice simulatorRelated tools and guides
Practice the skills that feed into the ICAO English assessment and the aptitude verbal tests used in airline selection.
Practice simulator
ICAO English practice simulator
Vocabulary, grammar, listening comprehension, timed speaking exercises and a self-assessed mock test covering all six rated skills. Free, no sign-up.
Aptitude exercise
Aviation English exercise
Timed aviation English reasoning exercise, training the skill the DLR test and other selection systems assess.
Aptitude exercise
Radio comprehension exercise
Short ATC audio clips with timed questions, training the same listening accuracy the comprehension rating measures.
Aptitude exercise
Verbal reasoning exercise
True/False/Cannot-Say verbal reasoning at aptitude-test pace, targeting the cognitive verbal format used in airline selection.
Free simulator
ATC communications simulator
Fly scripted ATC scenarios and read back clearances in ICAO phraseology, the same readback discipline the interactions rating measures.
Full hub
Pilot aptitude test practice
74 free exercises across all aptitude domains tested in airline selection: spatial, memory, attention, reasoning and more.
Frequently asked questions
Frequently asked questions
What is ICAO English Level 4?
How long is an ICAO English Level 4 endorsement valid?
How is ICAO English proficiency assessed?
What are the six skills rated in the ICAO English assessment?
What is the difference between ICAO English Level 5 and Level 4?
What is ICAO English Level 6?
How does ICAO English proficiency differ from pilot aptitude verbal tests?
How can I practice for the ICAO English assessment?
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Important information
This page is general educational information for student and licensed pilots and may go out of date. Language proficiency rules, their national administration, and approved testing bodies change over time and vary by competent authority. The summaries here follow the cited EASA and ICAO texts but are not legal advice. SkyStudy is an independent study aid, is not affiliated with ICAO, EASA, any competent authority, or any language testing body, and does not guarantee any assessment or licensing outcome. Always verify current requirements with your ATO and competent authority.
Last reviewed July 2026