Two tenses, one stem. The futur simple says what WILL happen; the conditionnel présent says what WOULD happen — and it's also the tense of politeness and hypothesis. Because they share a stem, learning one gives you the other almost for free.
1 · The shared stem
Both tenses are built on the same stem: the infinitive (for -re verbs, drop the final -e). Only the endings differ — the futur uses -ai/-as/-a/-ons/-ez/-ont, the conditionnel uses the imparfait endings.
| Person | Futur (will) | Conditionnel (would) |
|---|---|---|
| je | parlerai | parlerais |
| tu | parleras | parlerais |
| il / elle | parlera | parlerait |
| nous | parlerons | parlerions |
| vous | parlerez | parleriez |
| ils / elles | parleront | parleraient |
2 · Irregular stems (learn once, use for both)
These verbs change their stem — but the SAME stem powers both the futur and the conditionnel.
| Verb | Stem | Futur (je) | Conditionnel (je) |
|---|---|---|---|
| être | ser- | serai | serais |
| avoir | aur- | aurai | aurais |
| aller | ir- | irai | irais |
| faire | fer- | ferai | ferais |
| pouvoir | pourr- | pourrai | pourrais |
| vouloir | voudr- | voudrai | voudrais |
| devoir | devr- | devrai | devrais |
| savoir | saur- | saurai | saurais |
| voir | verr- | verrai | verrais |
| venir | viendr- | viendrai | viendrais |
| envoyer | enverr- | enverrai | enverrais |
| falloir | faudr- | il faudra | il faudrait |
3 · When to use the futur
Future facts and plans; after quand / lorsque / dès que when the action is in the future; and in the main clause after « si + présent ».
- Demain, il fera beau.Tomorrow it will be nice.
- Quand je serai grand, je voyagerai.When I'm grown up, I'll travel. (both clauses future → futur)
- Si tu viens, nous irons à la plage.If you come, we'll go to the beach. (si + présent → futur)
4 · When to use the conditionnel
Politeness and wishes, advice, hypothesis (after « si + imparfait »), and the future-in-the-past in reported speech.
- Je voudrais un café.I would like a coffee. (politeness)
- Tu devrais te reposer.You should rest. (advice)
- Si j'avais le temps, je lirais plus.If I had time, I would read more. (hypothesis)
- Il a dit qu'il viendrait.He said he would come. (future-in-the-past)
5 · The si-clause rule (don't get this wrong)
The verb right after « si » is never in the futur or the conditionnel. Match the pair correctly:
| Si-clause | Main clause | Example |
|---|---|---|
| présent | futur | Si tu étudies, tu réussiras. |
| imparfait | conditionnel | Si tu étudiais, tu réussirais. |
Common mistakes
Never use the conditionnel after « si »; the condition takes the imparfait.
After « quand » about the future, use the futur, not the conditionnel.
A polite request uses the conditionnel (voudrais), not the futur (voudrai).
The nous futur ending is -ons (finirons); -ont is for ils/elles (finiront).