This is one of the most diagnostic errors of an English-speaking learner of French. The English speaker writes Quand tu arrives, je serai content — and a French reader immediately knows the writer is not native, because that arrives should be arriveras. The rule is simple, but it cuts directly across an English habit so deep that even advanced learners trip on it: French uses the future tense after temporal conjunctions referring to the future, where English uses the present.
This page is about that rule, the conjunctions it applies to, and the related construction with the futur antérieur for completion. By the end, you will have an internal alarm that goes off whenever you write quand + a present tense in a future-reference sentence — and you will know how to fix it.
The core rule
When the action of the temporal clause refers to the future, French uses the future tense in both clauses — even though English uses present tense in the temporal clause.
| English | French |
|---|---|
| When you arrive, I will be happy. | Quand tu arriveras, je serai content. |
| As soon as he's here, we'll leave. | Aussitôt qu'il sera là, on partira. |
| When I'm grown up, I'll be a firefighter. | Lorsque je serai grand, je serai pompier. |
| As long as I live, I'll work. | Tant que je vivrai, je travaillerai. |
| Once you finish, you can leave. | Une fois que tu auras fini, tu pourras partir. |
Notice the pattern: English shows the future once (in the main clause); French shows it twice (in both clauses). English lets the temporal conjunction carry the future meaning, while French insists on marking it explicitly on the verb.
Why? French is more literal about temporality than English. If the action is in the future, it gets a future-tense verb, period. The temporal conjunction tells you the timing relationship; the verb tense tells you when the action takes place on the timeline. English collapses these two pieces of information into one (the conjunction), but French keeps them separate.
The conjunctions this applies to
The rule covers a specific set of temporal conjunctions. Memorise this list.
| Conjunction | Meaning | Register |
|---|---|---|
| quand | when | neutral, all registers |
| lorsque | when (slightly more formal) | formal, written |
| dès que | as soon as (immediate) | neutral |
| aussitôt que | as soon as (immediate, slightly literary) | formal, written |
| après que | after | neutral, formal |
| tant que | as long as | neutral |
| une fois que | once | neutral |
| pendant que | while | neutral |
| au moment où | at the moment that, just when | neutral, slightly literary |
All of these, when introducing a future-reference clause, take a future tense in French. That is the single rule. The variations come in which future tense — futur simple or futur antérieur — and we will get to that in a moment.
Examples with each conjunction
Quand tu arriveras, je serai content.
When you arrive, I'll be happy.
Lorsque je serai grand, je serai pompier.
When I'm grown up, I'll be a firefighter.
Dès qu'il sera là, on partira.
As soon as he's here, we'll leave.
Aussitôt qu'il fera jour, je me lèverai.
As soon as it's daylight, I'll get up.
Après que tu auras fini, on parlera.
After you've finished, we'll talk.
Tant que je vivrai, je travaillerai.
As long as I live, I'll work.
Une fois qu'on sera installés, je t'inviterai.
Once we're settled in, I'll invite you over.
Pendant que tu cuisineras, je mettrai la table.
While you cook, I'll set the table.
In every one of these sentences, English uses a present tense in the temporal clause and a future in the main clause; French uses a future in both. Practise reading these aloud in pairs (English / French) until the rhythm of the French version feels natural.
Two future tenses, two relationships
Now the next layer. French does not just use the future after these conjunctions — it chooses which future based on the timing relationship between the two clauses. There are two cases.
Case 1: simultaneous or unfolding actions → futur simple
When the two actions in the sentence are simultaneous or unfolding together, both clauses use the futur simple.
Quand tu arriveras, je serai à la maison.
When you arrive, I'll be at home. (the two states overlap)
Pendant que tu liras, je préparerai le dîner.
While you read, I'll make dinner. (the two activities run in parallel)
Tant qu'il pleuvra, on restera à l'intérieur.
As long as it rains, we'll stay inside. (durations overlap)
In each, both verbs are in futur simple because the two actions occupy the same future stretch of time. Neither one is finished before the other begins.
Case 2: one action completed before the other → futur antérieur in the temporal clause
When the action in the temporal clause is completed before the action in the main clause, the temporal clause takes the futur antérieur, and the main clause stays in the futur simple (or imperative).
Quand tu auras fini, on partira.
Once you've finished, we'll leave. (your finishing wraps up first)
Dès que j'aurai lu le livre, je te le prêterai.
As soon as I've read the book, I'll lend it to you.
Lorsque vous serez arrivés, on dînera ensemble.
When you (plural) have arrived, we'll have dinner together.
Aussitôt qu'il aura compris, il viendra.
As soon as he understands [completes the understanding], he'll come.
Une fois que nous aurons signé, on pourra commencer.
Once we've signed, we can begin.
The English equivalent often uses the present perfect (have finished, have read, have arrived) — which is itself a hint that completion-before is the meaning. Whenever English uses have + past participle in a future-time temporal clause, French is overwhelmingly likely to want the futur antérieur.
Side-by-side comparison
| Sentence | Tenses | Reading |
|---|---|---|
| Quand tu arriveras, je serai content. | futur simple + futur simple | Two states overlapping in the future. |
| Quand tu seras arrivé, on commencera. | futur antérieur + futur simple | Your arrival completes first; then we start. |
| Dès que tu finiras, je t'appelle. | futur simple + présent (casual) | The two actions are nearly simultaneous. |
| Dès que tu auras fini, je t'appellerai. | futur antérieur + futur simple | Your finishing is done; then I call. |
The imperative in the main clause
A common variant: the main clause is an imperative, not a futur simple. The rule still holds — the temporal clause takes the future tense.
Dès que tu auras fini, appelle-moi.
As soon as you've finished, call me.
Quand tu arriveras, envoie-moi un message.
When you arrive, send me a message.
Lorsque vous serez prêts, dites-le-nous.
When you're ready, let us know.
The imperative is grammatically present-tense, but functionally future-oriented (it asks the listener to do something in the future). The temporal clause still takes the future tense to mark its own future-time reference.
Si vs. quand: the rule split
A frequent point of confusion for learners: si and quand both translate to English when or if, but they behave very differently. Si introduces a condition (uncertain); quand introduces a time (assumed to occur).
- Si: the action might or might not happen. Always present tense in the si-clause when the main clause is future. Si tu viens, je serai content.
- Quand: the action will happen — only the timing is unknown. Future tense in both clauses. Quand tu viendras, je serai content.
Si tu viens demain, je serai content.
If you come tomorrow, I'll be happy. (uncertain whether you'll come)
Quand tu viendras demain, je serai content.
When you come tomorrow, I'll be happy. (you're definitely coming)
The two sentences look almost identical in English, but they convey different speaker stances. Si leaves room for the action not to happen; quand takes the action as given. And the tense rule splits accordingly: si + present, quand + futur. We treat the si-clause rule on the si-clauses page; the rule for quand and friends is what this page is about.
After-clauses: après que
Après que deserves a special note because it is the one conjunction in this group with a complication. Traditional grammarians once insisted that après que take the indicative (which it does — futur simple or futur antérieur in future contexts), but modern usage often pulls it toward the subjunctive, by analogy with avant que.
For learners, the safe rule:
- Future reference: après que
- futur simple or futur antérieur (more correct, what schoolbooks teach).
- Past reference: après que
- indicative (passé composé, plus-que-parfait), traditionally — though many speakers use the subjunctive here too.
Après que tu auras fini, on ira au cinéma.
After you've finished, we'll go to the cinema. (futur antérieur in the temporal clause)
Après qu'il sera parti, j'éteindrai la lumière.
After he leaves, I'll turn off the light.
In speech, you will sometimes hear après que + subjunctive (après qu'il soit parti). It is widespread, often accepted, but technically a deviation from prescriptive grammar. For learners, the indicative is the safer choice and matches what writing expects.
Past-reference temporal clauses: a note
The future-tense rule only applies when the temporal clause refers to the future. When the temporal clause refers to the past, French uses past tenses, the same as English.
Quand je suis arrivé, il dormait.
When I arrived, he was sleeping. (past, no future)
Dès qu'il est entré, on s'est levés.
As soon as he came in, we stood up.
Quand j'avais ton âge, on n'avait pas de portable.
When I was your age, we didn't have cell phones.
So the rule is more precise: after temporal conjunctions referring to the future, French uses a future tense in both clauses. Past-reference clauses follow ordinary past-tense rules.
A worked example: building a sentence step by step
Take the sentence I'll call you as soon as I've finished my work. The conjunction as soon as maps to dès que. The English present perfect I've finished signals completion before the main action, so the temporal clause takes the futur antérieur: j'aurai fini mon travail. The main clause I'll call you is futur simple: je t'appellerai. Assembled: Dès que j'aurai fini mon travail, je t'appellerai.
Now When you arrive, I'll be at the station. The conjunction is quand. The two actions are simultaneous, so both clauses take the futur simple: Quand tu arriveras, je serai à la gare.
Practising this decomposition — which conjunction? simultaneous or completion-before? which futur tense? — will internalise the rule within a few weeks of consistent attention.
A common subtlety: when both options are possible
Sometimes either futur simple or futur antérieur could fit, depending on whether the speaker wants to emphasise simultaneity or completion. Both versions are grammatical; the choice is one of meaning.
| French | English | Reading |
|---|---|---|
| Quand tu finiras, on partira. | When you finish, we'll leave. | The two actions run together — your finishing is the trigger that overlaps with our leaving. |
| Quand tu auras fini, on partira. | When you've finished, we'll leave. | Your finishing is fully wrapped up first; then we leave. |
In casual speech, French speakers often default to the futur simple even when completion is the implied reading. In writing, the futur antérieur is preferred for sequenced actions. Both are correct; the choice is one of register and emphasis.
Common Mistakes
Mistake 1: Using the present tense after quand for future events.
❌ Quand tu arrives, je serai content.
Incorrect — quand referring to a future event takes the future tense.
✅ Quand tu arriveras, je serai content.
When you arrive, I'll be happy.
Mistake 2: Using the present perfect after dès que.
❌ Dès que tu as fini, on partira.
Incorrect — for completion in a future context, French uses the futur antérieur, not the passé composé.
✅ Dès que tu auras fini, on partira.
As soon as you've finished, we'll leave.
Mistake 3: Confusing si and quand.
❌ Si tu viendras, je serai là.
Incorrect — never the future tense in a si-clause.
✅ Si tu viens, je serai là.
If you come, I'll be there.
✅ Quand tu viendras, je serai là.
When you come, I'll be there.
Mistake 4: Mixing tenses inconsistently.
❌ Quand tu arrives, je serai à la maison et on dînera ensemble.
Incorrect — once you start with quand + future, the rule applies to that clause; arrives must be arriveras.
✅ Quand tu arriveras, je serai à la maison et on dînera ensemble.
When you arrive, I'll be home and we'll have dinner together.
Mistake 5: Using subjunctive after dès que / quand.
❌ Dès que tu sois là, on partira.
Incorrect — these conjunctions take the indicative, not the subjunctive. (Avant que takes the subjunctive; dès que does not.)
✅ Dès que tu seras là, on partira.
As soon as you're here, we'll leave.
Key takeaways
After the temporal conjunctions quand, lorsque, dès que, aussitôt que, après que, tant que, une fois que, pendant que, French uses the future tense when the action refers to the future — even though English uses the present.
The choice between futur simple and futur antérieur in the temporal clause depends on the timing relationship: simultaneous or unfolding actions take futur simple; one action completed before another takes futur antérieur.
For English-speaking learners, this is the single biggest tense-choice trap, because the English habit of using the present tense after when and as soon as is so deep. Train yourself with the rhythm: future + future (simultaneous) or futur antérieur + futur simple (sequenced). Watch for quand, lorsque, dès que in your writing, and check the tense every time. After a few weeks of conscious correction, the rule becomes automatic.
Now practice French
Reading grammar gets you part of the way. The exercises are where it sticks — free, no signup needed.
Start learning French→Related Topics
- Le Futur: OverviewA1 — French has two main futures — the synthetic futur simple (je parlerai) and the analytic futur proche (je vais parler) — plus the futur antérieur (j'aurai parlé) for completed future actions. This page maps how each is built, when each is used, and how they divide up the future-time space.
- Les Emplois du Futur SimpleA2 — The full range of uses of the futur simple — from confident predictions and solemn promises to soft commands, journalistic announcements, and the inferential 'must be'. When to choose futur simple over futur proche, and what each carries that the other does not.
- Le Futur AntérieurB1 — The future perfect of French — the 'will have done' tense. How to form it, when to use it (especially after quand, dès que, lorsque), and how it pairs with the futur simple to mark which future action finishes first.
- Présent ou Futur pour Parler du FuturA2 — When French uses the present tense for future events — and when it uses the futur proche or futur simple instead. The three-way competition for future meaning, with situational rules and natural examples.
- Le Conditionnel in Si-Clauses: Type 2, Type 3, and Mixed ConditionalsB1 — How the conditionnel pairs with the imparfait and plus-que-parfait to express counterfactual hypotheses about the present and the past — plus the mixed pattern, the universal English-speaker error to avoid, and the schoolyard rhyme that locks the rule in.