Subjunctive after Conditional Conjunctions: à condition que, à moins que, pourvu que

French has a whole family of conditional conjunctions beyond the familiar si — à condition que, pourvu que, à moins que, à supposer que, pour peu que — and they all behave differently from si in one crucial respect: they take the subjunctive. Si keeps the indicative; everything else in this neighborhood takes the subjunctive. Mastering this list is one of the more useful expansions of B1 grammar, because the alternatives let you express finer shades of conditionality than si alone — provided that, unless, supposing, as long as, I just hope — each with its own pragmatic flavor.

This page works through the main conjunctions, explains why their grammar differs from si's, and devotes special attention to pourvu que, which has the unusual property of being able to stand alone as a wish or a hope.

Why these conjunctions take the subjunctive (and si does not)

A useful way to see why si is the odd one out is to think about what each conjunction is doing semantically.

Si introduces a simple condition — a protasis, in linguistics terminology — and the language treats the protasis as setting up a hypothetical that the speaker is exploring as if it were real, just for the duration of the clause. The verb stays in the indicative because the speaker is pretending, for argument's sake, that the condition holds.

À condition que, pourvu que, à moins que, à supposer que, and the rest of the family go further. They explicitly mark the embedded clause as hypothetical, conditional, or excluded — they do not pretend the condition is true; they explicitly flag it as not-yet-asserted. The subjunctive is the morphological reflection of that flagging.

This is not a perfectly clean distinction in every textbook account, but it captures the working intuition: si lets the speaker lean into the hypothesis as if it were a fact for the sake of the argument; the subjunctive-taking conjunctions hold the hypothesis at arm's length and mark it explicitly as merely posited.

À condition que: provided that

À condition que corresponds closely to English "provided that" or "on the condition that." It introduces a stipulation that must be met for the main clause to hold.

The construction is rigid: à condition que + subject + verb in subjunctive. There is no version with the indicative. Note also the variant à condition de + infinitive for same-subject cases:

The same-subject collapse to à condition de + infinitive parallels pour / pour que and avant de / avant que: it is the standard French economy principle.

Pourvu que: provided that, as long as — and "I hope!"

Pourvu que has two distinct uses, and both take the subjunctive.

Pourvu que as a conditional conjunction

In its conditional use, pourvu que means "provided that" or "as long as." It is close in meaning to à condition que but feels slightly more colloquial and emphasizes a minimal sufficient condition.

The semantic shade compared with à condition que: à condition que often signals a more contractual or formal stipulation; pourvu que often signals a more relaxed, "as long as that's the case, we're good" tone.

Pourvu que as a free-standing wish

The more striking use of pourvu que is exclamatory: a free-standing clause expressing a wish or a hope, with no main clause attached.

This use is everyday colloquial French. Pourvu que ça marche ! is something you say while pressing the start button on a temperamental machine; pourvu qu'il fasse beau ! is what you mutter looking at a cloudy sky on the morning of an outdoor wedding. The exclamation point at the end is more than punctuation — it is structurally part of how this construction is used. Without it, the clause feels grammatically incomplete because the listener expects a main clause to follow.

The wish-use of pourvu que belongs to a small family of French constructions where an embedded que-clause stands alone as a free-standing utterance — see the page on other subjunctive-triggering conjunctions for the related uses of que + subjunctive on its own.

À moins que: unless

À moins que corresponds to English "unless" — it introduces an exception that, if it occurs, would block the main clause.

The same optional ne explétif that we saw with avant que appears here too:

The ne is not a negation — à moins qu'il ne pleuve and à moins qu'il pleuve mean exactly the same thing. The ne belongs to a more formal register and is freely droppable in casual speech. As with avant que, modern usage permits both forms; the bare version (without ne) is more common in conversation.

A useful note: à moins que with the ne explétif can momentarily look like a negation to learners, especially in writing. Train your eye to recognize ne without pas as the formal stylistic ne, not a real negation.

The same-subject form is à moins de + infinitive:

Supposé que / à supposer que / en supposant que: supposing that

This trio of conjunctions all mean "supposing that" — they introduce a hypothetical premise for the sake of argument.

• Supposé que — slightly archaic, more written
• À supposer que — neutral, common in argumentation
• En supposant que — slightly more formal

All three take the subjunctive.

These conjunctions are particularly common in argumentative or analytic prose — debates, policy discussions, philosophical reasoning — where you want to entertain a premise without endorsing it. In casual speech, they sound a touch formal; in writing, they are everyday.

Pour peu que: provided that, if even slightly

Pour peu que is more idiomatic and less common than the others, but worth knowing because it appears regularly in writing. It means "provided that" or "if only ever so slightly," with a flavor of "the smallest amount of X is enough."

The construction implies a low threshold: a tiny amount of the condition is enough to trigger the consequence. This shading distinguishes it from à condition que (a stipulated condition) and pourvu que (a sufficient condition).

Comparison: si vs. the subjunctive-taking conjunctions

Here is the moment to look at si alongside its subjunctive cousins so the contrast is clear.

A reminder: au cas où is the odd one out in another direction — it takes the conditionnel, not the subjunctive and not the indicative. Au cas où il viendrait — "in case he comes." This is covered in the conditional pages; we mention it here only to flag that "in case" does not pattern with the subjunctive-takers.

The four sentences describe slightly different conditional relationships, and the four moods (indicative, subjunctive, subjunctive with ne explétif, conditional) are part of how the language signals those differences.

How French differs from English

English builds all of these conditional notions with the indicative or with simple modal verbs. Provided that he comes (indicative), unless it rains (indicative), supposing he's right (indicative). The conjunction does the semantic work; the verb form does not change.

French splits this work between the conjunction and the mood. The conjunction signals which kind of conditional relationship is in play (stipulation, exception, supposition), and the mood signals that the embedded clause is hypothetical rather than asserted. This double signaling is what makes the French conditional system feel finer-grained than the English one — and what makes the morphology obligatory in places where English speakers are tempted to leave the verb in its default form.

A useful drill: take any English "provided / unless / supposing" sentence and translate it twice. First, identify the conjunction (à condition que, à moins que, à supposer que); second, conjugate the verb in the subjunctive. This double step is the workflow you need to internalize.

Common Mistakes

Mistake 1: Using the indicative after à condition que.

The English "provided you come" gives no signal of any subjunctive, and English speakers slip into the indicative by default. Drill à condition que tu viennes, à condition qu'il vienne, à condition qu'on vienne until the subjunctive feels automatic.

Mistake 2: Using si with the subjunctive.

A common over-correction: learners hear that conditional conjunctions take the subjunctive and apply it to si. Si is the exception — it always takes the indicative (or in counterfactuals, the imparfait or plus-que-parfait, but never the subjunctive present).

Mistake 3: Treating à moins que's ne explétif as a real negation.

The ne explétif (just ne, not ne...pas) is non-negative. If you want "unless it doesn't rain," you would say à moins qu'il ne pleuve pas, but this is a strange thing to want to say. In normal usage, the optional bare ne with à moins que does not negate.

Mistake 4: Confusing au cas où with à condition que.

Au cas où is the only common conditional conjunction that takes the conditionnel. Do not lump it with the subjunctive-takers. Au cas où + conditionnel is its own distinct construction.

Mistake 5: Using pourvu que + indicative for the wish reading.

The wish use feels conversational and might tempt learners to drop the subjunctive in favor of an everyday-feeling indicative. Resist. The subjunctive is what makes the construction grammatical and what gives it the slightly heightened, exclamatory feel.

Key takeaways

• À condition que, pourvu que, à moins que, à supposer que, en supposant que, and pour peu que all trigger the subjunctive.
• Si is the major exception in the conditional family — it always takes the indicative.
• Au cas où takes the conditionnel, not the subjunctive — the only common conditional conjunction to do so.
• The ne explétif with à moins que is optional and non-negative. À moins qu'il (ne) pleuve — both versions are correct.
• Pourvu que has a striking exclamatory use as a free-standing wish: Pourvu qu'il fasse beau ! — "I just hope the weather's nice!"
• Same-subject reductions exist for several of these: à condition de
  • infinitive, à moins de
    • infinitive. Use them when the subjects match.
• These conjunctions express finer shades of conditionality than si alone — provided, unless, supposing, as long as. Each has a distinct pragmatic flavor; learning the family expands your conditional toolkit considerably.