Règles d'Apostrophe: élision

The apostrophe in French has one main job: it marks elision, the dropping of a final vowel before another vowel-initial word. Je aime becomes j'aime. Le homme becomes l'homme. Ne ai pas becomes n'ai pas. This is not a stylistic option — it is obligatory in writing whenever the conditions are met. Failing to elide is a spelling error in French in exactly the same way as failing to use an apostrophe in English don't is an error.

This page covers which words elide, when elision happens, the silent-h that allows it and the aspirated-h that blocks it, the special case of si (which elides only before il/ils), and the few lexicalized contractions like aujourd'hui where the apostrophe is frozen inside a single word.

What elision does

French has a strong dislike of hiatus — two vowels meeting across a word boundary. To prevent it, a fixed set of short function words drops its final vowel and attaches to the following word with an apostrophe.

Without elision, you'd get sequences like je ai, le ami, de un, que il. French has resolved every one of these by elision: j'ai, l'ami, d'un, qu'il.

Two elisions: je → j' before ai, le → l' before avion. Both are obligatory; without them the sentence would be ungrammatical in writing.

The list of elidable words

Only a closed set of words elide. Memorize this list — there are no others.

Words not on this list do not elide, even before a vowel. Notably:

• tu does not elide in standard writing. Tu as stays tu as. (The casual spoken contraction t'as exists, but it is informal and is mostly avoided in standard written French.)
• il, elle, on do not elide. Il a, elle a, on a stay full.
• mon, ton, son do not elide — they have their own euphony rule (using the masculine form before vowel-initial feminine nouns: mon amie, not m'amie). See determiners for that rule.
• ma, ta, sa do not elide — they get replaced by mon, ton, son before vowels.

Tu stays full; que elides to qu' before il; il itself stays full.

Vowel or silent h: what triggers elision

Elision is triggered when the next word begins with either of two things:

1. A vowel letter: a, e, i, o, u, y.
2. A silent (mute) h, which is treated as if it weren't there.

The vowel case is simple. The silent-h case requires a French-specific distinction.

Silent h vs aspirated h

French has two kinds of h, both completely silent in pronunciation. The difference is whether they "act invisible" or "act like a consonant" for elision and liaison purposes.

• H muet (silent / mute h): inherited from Latin words. The h is invisible — words behave as if they started with the vowel. Elision and liaison apply.
• H aspiré (aspirated h — a misleading traditional name, since nothing is actually aspirated): inherited mainly from Germanic, Scandinavian, or onomatopoeic words. The h blocks elision and liaison even though it isn't pronounced.

Two h-words: honte and héros are both h aspiré. We write la honte (not l'honte) and le héros (not l'héros).

There is no rule for predicting which is which — it depends on the word's etymology. The standard recommendation: in dictionaries, h aspiré is marked with an asterisk () or a dagger (†) before the entry. Learners memorize the most common *h aspiré words and treat everything else as h muet.

The most frequent h aspiré words to remember:

hache (axe), hasard (chance), haine (hatred), hauteur (height), hêtre (beech), héros (but not héroïne or héroïque, which are h muet!), honte (shame), hibou (owl), hors (outside), hurler (to scream), huit (eight — we write le huit, not l'huit; in compounds like dix-huit, the x of dix attaches via liaison /diz‿ɥit/, but that's liaison, not elision).

The special case of si

The word si ("if") elides only before il and ils, and nowhere else.

• S'il vient — yes (s' before il)
• S'ils viennent — yes (s' before ils)
• Si elle vient — no, no elision (the rule is specifically about il/ils)
• Si on part — no, no elision (on starts with a vowel but si doesn't elide here)
• Si Anne arrive — no, no elision

Why this asymmetry? Historical accident — si + il contracted to s'il very early in the language, while si elle didn't develop a contraction because the e of elle was easily pronounceable in sequence with the i of si. The asymmetry was preserved by usage and codified by grammarians. There is no logical reason; it just is.

Lexicalized contractions

Some apostrophes have become frozen inside single words through historical contractions. They are now spelled as one word with an apostrophe.

For quelqu'un, note: the masculine form quelqu'un has a fixed apostrophe; the plural quelques-uns uses a hyphen, not an apostrophe.

A note on typography

In careful printed French, the apostrophe is the typographic apostrophe ’ (U+2019), not the straight ASCII apostrophe ' (U+0027). Word processors typically auto-substitute. For digital text, the straight apostrophe is universally accepted; the curly one is preferred in print and high-quality typography.

There is no space around the apostrophe: write l'eau, not l' eau or l 'eau. This is one of the most common typos by non-native speakers using word-processing software set to a different language.

Source-language comparison

English has its own apostrophe system, but it does different work from the French one. English apostrophes mark contractions (don't, won't, it's) and possession (John's car). French apostrophes mark only elision — never possession. (French possessives use de: la voiture de Jean, not Jean's voiture.)

The closest English equivalent to French elision is the spoken-language contraction I'm, you're, isn't. But English contractions are optional in writing — you can choose to write I am or I'm. French elision is mandatory: there is no choice between je ai and j'ai. Only j'ai is grammatical.

For Spanish speakers, French elision is initially surprising because Spanish doesn't use apostrophes at all. Spanish tolerates hiatus (la amiga, de un, que él) and writes everything out. French insists on elision wherever the rules say so.

Common Mistakes

Key takeaways

• French elision drops the final vowel of a small set of short words before a vowel-initial or silent-h-initial word, and replaces it with an apostrophe.
• The elidable words are: le, la, je, me, te, se, de, ne, que, ce, si, jusque (plus a few others in restricted contexts).
• Elision is mandatory in writing, not optional. Je ai is not a spelling variant — it is a misspelling.
• Elision applies before vowels and silent h (h muet) — l'homme, l'heure, l'hôtel.
• H aspiré blocks elision even though the h itself is silent — le héros, la honte, le hibou. The list is etymological and must be memorized.
• Si elides only before il and ils — s'il, s'ils. Not before elle, elles, on, Anne.
• Some apostrophes are frozen inside single words: aujourd'hui, quelqu'un, presqu'île.
• No space around the apostrophe: l'eau, never l' eau.