Il faut is one of the most frequently used expressions in French. It comes from the verb falloir, an impersonal verb that exists only in the il form, and it translates most naturally as “it is necessary,” “one must,” or simply “you have to,” depending on context. Because it’s impersonal, it never changes to agree with a subject the way most French verbs do. There’s no je faux, no nous fallons. There’s only il faut.
This single construction does the work of several different English phrases, and it appears in three distinct grammatical patterns: followed by a noun, followed by an infinitive, or followed by que and the subjunctive. Understanding the difference between these patterns, and when to use each, is what this lesson covers.
Pattern 1: Il faut + Noun
The simplest use of il faut is with a noun, expressing that something is needed or required.
Il faut du temps. (“Time is needed.” / “It takes time.”)
Il faut de la patience. (“Patience is necessary.”)
Il faut de l’argent. (“Money is needed.”)
Notice that the noun is introduced with a partitive article (du, de la, de l’) when referring to uncountable things, and with an indefinite article (un, une, des) when referring to countable ones.
Il faut un passeport pour entrer dans ce pays. (“A passport is needed to enter this country.”)
Pattern 2: Il faut + Infinitive
More often, il faut is followed directly by an infinitive. This construction expresses a general obligation: something “one must” or “people need to” do, without specifying who.
Il faut partir. (“It’s time to leave.” / “We need to leave.”)
Il faut manger pour vivre. (“One must eat to live.”)
Il faut travailler dur. (“You have to work hard.”)
Because the infinitive construction is general, it doesn’t point to any specific person. This is the key distinction between Pattern 2 and Pattern 3 below: if you need to specify who must do something, you’ll need to switch to the subjunctive.
Pattern 3: Il faut que + Subjunctive
When the obligation applies to a specific person or group, use il faut que followed by the subjunctive. This is the most personal of the three constructions: it says not just that something must happen in general, but that a particular someone must do it.
Il faut que nous partions. (“We need to leave.”)
Il faut que tu fasses tes devoirs. (“You need to do your homework.”)
Il faut qu’elle prenne une décision. (“She needs to make a decision.”)
If you need a refresher on how the French subjunctive works and how to form it, the linked post covers it in full. For quick reference, here are the present subjunctive forms of the two most common verbs, être and avoir, since they’re irregular and come up constantly with il faut que:
| Être (Present Subjunctive) | |
|---|---|
| que je sois | que nous soyons |
| que tu sois | que vous soyez |
| qu’il/elle/on soit | qu’ils/elles soient |
| Avoir (Present Subjunctive) | |
|---|---|
| que j’aie | que nous ayons |
| que tu aies | que vous ayez |
| qu’il/elle/on ait | qu’ils/elles aient |
Adding a Specific Person: Indirect Object Pronouns with il faut
There’s a fourth variation worth knowing. You can place an indirect object pronoun before il faut + infinitive to indicate who specifically must do something. This construction is an alternative to the il faut que + subjunctive pattern, and the two are often interchangeable.
Il nous faut partir. (“We need to leave.”)
Il me faut trouver une solution. (“I need to find a solution.”)
Il leur faudra revenir demain. (“They’ll need to come back tomorrow.”)
The pronoun goes between the subject il and the verb faut, a placement that feels unusual if you’re used to thinking of object pronouns always coming right before the main verb. Here, faut is the main verb, so the pronoun lands directly in front of it.
Falloir in Other Tenses
Because falloir is a real verb (even if an impersonal one), it conjugates across tenses. The stem changes, but the impersonal il subject never does.
| Tense | Form | Meaning |
|---|---|---|
| Present | il faut | it is necessary / one must |
| Imperfect | il fallait | it was necessary / one had to |
| Passé composé | il a fallu | it was necessary (completed) |
| Future | il faudra | it will be necessary / one will have to |
| Conditional | il faudrait | it would be necessary / one would have to |
Each of these follows the same three patterns above: noun, infinitive, or que + subjunctive.
Il fallait partir tôt. (“It was necessary to leave early.”)
Il a fallu trois mois pour finir le projet. (“It took three months to finish the project.”)
Il faudra que tu sois là à midi. (“You’ll need to be there at noon.”)
Il faudrait être certain que ce soit la bonne décision. (“We would need to be sure it’s the right decision.”)
Choosing Between the Infinitive and the Subjunctive
The practical question learners run into is: when should I use il faut + infinitive versus il faut que + subjunctive?
- Use the infinitive when the statement is general, when no specific subject is implied, or when the obligation applies to “people in general.”
- Use que + subjunctive (or the indirect object pronoun variation) when you need to make clear who specifically must do something.
Compare:
Il faut dormir assez. (“One needs to sleep enough,” general truth)
Il faut que tu dormes assez. (“You need to sleep enough,” directed at someone specific)
In spoken French, the infinitive construction is often used even when a specific person is implied, relying on context to make things clear. The subjunctive construction is more formal and unambiguous.
Related Expressions of Necessity
Il faut is the most common way to express necessity in French, but it has company. The following expressions follow the same que + subjunctive pattern and carry similar meanings:
| Expression | Meaning | Example |
|---|---|---|
| il est nécessaire que | it is necessary that | Il est nécessaire que vous parliez français. |
| il est important que | it is important that | Il est important qu’elle comprenne. |
| il est indispensable que | it is essential that | Il est indispensable que nous arrivions à l’heure. |
| il vaut mieux que | it is better that | Il vaut mieux qu’il reste ici. |
All of these require the subjunctive in the clause that follows que.
What to Practice Next
Il faut shows up constantly in real French: in instructions, advice, warnings, and everyday conversation. The fastest way to internalize all three patterns is through speaking practice, where you’re forced to produce the right construction on the spot rather than choosing it from a multiple-choice list.
If you want to work on the subjunctive forms triggered by il faut que, the post on the French subjunctive walks through the full conjugation. And since il faut sits right alongside devoir and pouvoir as a core expression of obligation and ability, the lesson on French -oir verbs is a useful companion.
One of the best ways to get these constructions to stick is to use them in actual conversation, explaining to a French speaker what you need to do, what you think they should do, or what has to happen next. Mondly builds structured speaking practice into every lesson, which makes it a practical tool for drilling constructions like il faut in context rather than in isolation.
