ICAO Rating Scale: What is Fluency?

Fluency is one of 6 ICAO language proficiency rating scale requirements, therefore, it has to be discussed in detail on my website. I need to emphasize this article is only an introduction to the matter of fluency. Now I would like to split the Fluency section into two smaller parts – the former will pay a closer attention to the ability to speak at a natural tempo; the latter will take into consideration discourse markers but in a separate article. As always I focus solely on this part of the table with the passing grades. Take a look at the table below to check what are you obliged to know.






LEVEL 6 Expert

Able to speak at length with a natural and effortless flow

Varies speech flow for stylistic effect, e.g. to emphasize a point

Uses appropriate discourse markers and connectors spontaneously



Able to speak at length with relative ease on familiar topics

May not vary speech flow as a stylistic device

Can make use of appropriate discourse markers





Produces stretches of language at an appropriate tempo


There may be an occasional loss of fluency on the transition from rehearsed or formulaic speech to spontaneous interaction, but this does not prevent effective communication


Can make limited use of discourse markers or connectors. Fillers are not distracting.

*) I created this table with a support of ICAO 9835 Document, page “The Rating Scale”, section “Fluency”

What is Fluency?

According to Cambridge Online Dictionary fluency is defined as: (1) “When a person is fluent, they can speak a language easily, well, and quickly”, (2) “When a language is fluent, it is spoken easily and without many pauses”. Which one of these is more important? In fact, both of them, incorporated, give you the best definition. You, as a candidate, have to speak with ease and quickly. However, you shouldn’t speak too fast. The matter of pauses is also underlined, hence the lesser you hesitate and reduce the number of pauses you make, the better your fluency will be assessed. Slowness is not acceptable unless a non-passing grade Level 3 Pre-Operational is satisfactory for you but I truly doubt it. If the use of “fillers” (“uh”, “um”, etc.) distract your message you can also expect the negative final result.

Fluency for ICAO requirements

Fluency Level 4 Operational

“Produces stretches of language at an appropriate tempo. There may be an occasional loss of fluency on the transition from rehearsed or formulaic speech to spontaneous interaction, but this does not prevent effective communication.”

(I intentionally omit the matter of discourse markers; I’ll write a separate article about them and their importance in a speaking part of an exam.)
Well, well, well. What do we have here? Oh, this phrase “stretches of language” seems intriguing, isn’t it? 😉 A stretch of language is an utterance longer than a single word, for example, sentence or phrases. If you say something longer than one word, it is a stretch of language. What is “appropriate tempo”? You should speak naturally; your speech should not be either too slow or too fast. You are allowed to occasionally lose fluency (“on the transition from rehearsed or formulaic speech to spontaneous interaction”). “Formulaic speech” (which contains repeated ideas or words) and “rehearsed speech” (it is said with all the details). In my opinion, your fluency can slightly deteriorate once there is a transition from rich in detail description to a “spontaneous interaction” (meaning natural and done without any planning).

Fluency Level 5 Extended

“Able to speak at length with relative ease on familiar topics but may not vary speech flow as a stylistic device.”

You are required to speak with ease so effortlessness on a vast spectrum of topics is a must. Your tempo allows you to communicate effectively on advanced subjects.

“(…) you may not vary speech flow as a stylistic device.”

Stylistic devices sound creepy here but they aren’t difficult because you surely know some of them intuitively but you may not be conscious they function under the name “stylistic devices” or “figures of speech”. First of all, let me recall the definition: they are used to “provide emphasis, the freshness of expression, or clarity.” I would like to emphasize here this subject will be also discussed on my website because a short mention here may not be satisfactory for those who want to inquire into this aspect of fluency. One of the well-known stylistic devices is a euphemism which is used to replace something which is expressed directly, often in an ordinary manner, or it may be a taboo; you intentionally provide your interlocutor with a more polite synonym which requires speaker’s intelligence and a wide spectrum of phrases and grammar structures. A euphemism for a verb “to die” is “to pass away” or “not regain consciousness” – depending on a situation. As I mentioned earlier, I’ll pay more attention to stylistic devices. Let me know by e-mail if you need this article faster so I’ll be motivated to write it as soon as possible 🙂

Fluency Level 6 Expert

“Able to speak at length with a natural, effortless flow. Varies speech flow for stylistic effect, e.g. to emphasize a point.”

You can speak with ease at any subject and make logic and interesting sentences. What is more, your speech flow is well organized and supported with stylistic effects. Two keywords here are “effortless” and “varies” which I would transform into “a variety”; they two give the best view what a Level 6 should be.

ICAO holistic descriptors

What Can Negatively Affect Your Fluency?

In my opinion, it is the lack of self-confidence that has the most significant impact on your general score. Students tend to overthink the structures and their correctness and they often don’t have a clear and well-organized speech plan. It is fine when you’re doing it with your teacher during your English classes because you need some time for the language acquisition and revision. However, if you haven’t practiced before an exam, your fluency undoubtedly would have reflected your insecurities, doubts, and fears. Your preparation really matters so take an advantage of studying or refreshing whenever you’re exposed to the English language. Push yourself to the limits and try to focus on the ambitious teaching materials. If you have no idea where to find them, please let me know by email – I’ll send you some links and my answers to your questions.


As I mentioned earlier, this blog post is only an introduction to this vast subject and remember to join my newsletter to be informed when discourse markers article will be published. What are your experiences with fluency? How did you perform with that requirement during an exam? Let me know in the comments below. Should you have a useful piece of advice on the best methods to study fluency that wasn’t covered here – please don’t hesitate to share your opinion!

ICAO examination