French silent letters and liaison: which letters do you say?
In French, most consonants written at the end of a word are not pronounced: the T of petit, the D of grand, the S of vous. But when the next word begins with a vowel, that silent consonant often comes back to life and attaches to the front of the next word. That is liaison, and it is why spoken French does not sound like written French.
The default is silence
Say 'petit'. It ends on the vowel — 'puh-TEE'. The T is written and not spoken. Same with the D of 'grand', the S of 'vous', the T of 'tout', the X of 'deux', the plural S on almost every noun.
This is the normal case, not the exception. French spelling froze centuries ago while the pronunciation kept moving, and the endings fell off the spoken language without ever leaving the page.
A few final consonants usually do survive, and the traditional memory hook is the word CaReFuL: c, r, f, l. 'Avec', 'pour', 'chef', 'seul' all end on a real consonant. Like every French spelling rule this one leaks — the R of 'parler' is silent, and so is the C of 'blanc' — but it will get you further than guessing.
Liaison brings the letter back
Now put a vowel after the silent letter and it reappears, attached to the next word rather than its own.
'les' on its own ends in a vowel sound. 'les chats' keeps it silent, because 'chats' begins with a consonant. 'les amis' does not: the S wakes up, turns into a Z, and lands on the front of the next word — 'lay-ZAH-mee'.
The consonant does not stay with the word it belongs to. It jumps. 'un petit ami' comes out as 'un puh-tee-TAH-mee', with the T starting the last syllable. This is why beginners cannot find the gaps between French words: the gaps are not where the spelling says they are.
Two of these letters change sound when they wake up. Written S and X become a Z sound. Written D becomes a T sound: 'un grand homme' has a T in the middle of it.
When liaison happens, and when it doesn't
You do not need the full rulebook to start. Liaison happens inside tight grammatical units, where two words function almost as one.
After a determiner: les amis, un enfant, ces hommes, mon ami. After a short adjective before its noun: petit ami, grand homme, bon élève. After a pronoun before its verb: nous avons, vous êtes, ils ont, on a. After short prepositions and adverbs: en avion, dans un, très intéressant, chez elle.
It does not happen after a singular noun ('un enfant intelligent' — no liaison on the noun), after 'et' ever, or across a real pause. 'Et' never links: 'et alors' keeps its gap, always.
There is also a set of words spelled with H that behave like consonants and block liaison — 'les héros' has no liaison, while 'les hommes' does. There is no way to hear the difference; it is learned word by word.
Why this matters for listening, not just speaking
Most learners meet liaison as a speaking rule and underestimate what it does to comprehension.
When a French speaker says 'ils ont un ami', the sound stream is 'eel-zon-tuh-nah-mee'. Every word boundary has moved. If you are listening for the shapes you saw on the page, you will hear nothing you recognize — not because it was fast, but because the syllables were rebuilt.
The fix is to practice hearing chunks instead of words. Take a short phrase, say it as one unbroken unit, and only then look at how it is spelled. 'Nous avons' is two written words and one spoken shape. 'Vous êtes' is another.
Missing a liaison rarely stops you being understood. But inserting one where it does not belong, or pronouncing a final consonant that should stay silent, is more noticeable — it is the equivalent of over-enunciating in English.
How to practice it
Start with the fixed phrases. There are maybe thirty combinations that carry most of the liaison you will ever need: nous avons, vous avez, ils ont, elles ont, on a, c'est un, dans un, en avion, très important, les autres, mon ami, deux ans.
Drill each as a single word. Do not say the two halves separately and then glue them; learn the fused shape from the start.
Then take the silent-letter side on its own. Say 'petit', 'grand', 'tout', 'vous' and cut the sound dead after the vowel. English speakers have a strong habit of releasing final consonants, so this feels unfinished at first. It should.
When you record words in TonePerfect, each word is scored sound by sound, and the sounds are ranked weakest-first — which is a useful way to check whether the final consonant you think you are dropping is actually gone.
Try these words
Tap to hear each one, then record yourself and see how they score.
Questions
Is liaison optional?+
Some of it is required, some is forbidden, and a large middle group is optional and depends on how formal the speech is. News readers and public speakers use more liaison than people in a café. Learn the required ones first — after determiners, pronouns, and short adjectives — and let the optional ones come with exposure.
Why does the S sound like a Z?+
Because the consonant is now sitting between two vowels, and French voices consonants in that position. The same happens with X: 'deux amis' has a Z sound in the middle. Written D goes the other way and comes back as a T.
How do I know if an H blocks liaison?+
You cannot tell from the spelling or the sound — both types of H are equally silent. Dictionaries mark the blocking ones, often with an asterisk or a superscript symbol. In practice you learn them as vocabulary: les héros and le héros block it, les hommes and l'homme do not.
Should I pronounce final consonants when speaking slowly?+
No. Slowing down does not bring silent letters back; it just gives you more time on the vowels. A slowly spoken 'petit' still ends on the vowel. The only thing that brings the consonant back is a following vowel in a liaison context.
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