Future Perfect in French

In Brief

The French futur antérieur usually means “will have done”: J'aurai fini avant midi (“I will have finished before noon”). Form it with the simple future of avoir or être, followed by a past participle (a verb form such as fini, “finished”). It can also express a conclusion about the past: Il aura oublié can mean “He must have forgotten.”

Overview

The futur antérieur looks forward to a point at which an action will already be complete. It therefore places one future event before another future event or deadline: Quand tu arriveras, je serai parti (“When you arrive, I will have left”). The departure is future from the speaker's point of view, but it happens before the arrival.

This B2 tense builds directly on two systems you may already know: the simple future forms of avoir and être, and the past participles used in compound tenses such as the passé composé. A compound tense is simply a tense made with an auxiliary or “helper” verb plus a participle.

French also uses the same form to make a likely deduction about something that has already happened. In that use, English often prefers “must have,” “probably,” or “will have” rather than a literal future. Context tells you whether Elle se sera trompée predicts a completed future mistake or concludes that “She must have made a mistake.”

How It Works

The basic pattern

The structure is:

subject + future of avoir or être + past participle

Most verbs use avoir. The auxiliary itself carries the future endings; the main verb stays in its past-participle form.

Person	avoir in the future	Example with finir	être in the future	Example with partir
je	aurai	j'aurai fini	serai	je serai parti(e)
tu	auras	tu auras fini	seras	tu seras parti(e)
il / elle / on	aura	il aura fini	sera	elle sera partie
nous	aurons	nous aurons fini	serons	nous serons parti(e)s
vous	aurez	vous aurez fini	serez	vous serez parti(e)(s)
ils / elles	auront	ils auront fini	seront	elles seront parties

The choice between avoir and être follows the same rules as in the passé composé. Most verbs take avoir: j'aurai mangé, nous aurons compris. A group of intransitive movement or change-of-state verbs—verbs used here without a direct object—take être, including aller, arriver, entrer, partir, rester, tomber, venir, naître and mourir. All pronominal verbs, whose infinitive includes se or s', also take être: elle se sera levée.

Some verbs can switch auxiliary according to how they are used. For example, sortir takes être when it means that the subject went out, but avoir when it has a direct object (the person or thing directly affected by the action):

• Elle sera sortie avant huit heures. — She will have gone out before eight.
• Elle aura sorti les poubelles avant huit heures. — She will have taken out the bins before eight.

Forming the past participle

Regular participles follow familiar patterns:

Infinitive	Ending change	Past participle	Future perfect example
parler	-er → -é	parlé	nous aurons parlé
finir	-ir → -i	fini	tu auras fini
vendre	-re → -u	vendu	ils auront vendu

Common irregular participles include eu (avoir), été (être), fait (faire), dit (dire), écrit (écrire), pris (prendre), mis (mettre), vu (voir), lu (lire), ouvert (ouvrir), venu (venir) and mort (mourir).

Agreement of the past participle

With être, the past participle normally agrees in gender and number with the subject:

• Marc sera arrivé.
• Léa sera arrivée.
• Marc et Léa seront arrivés.
• Léa et Inès seront arrivées.

With avoir, the participle normally does not agree with the subject: Elle aura terminé and Ils auront terminé. It does agree with a preceding direct object, however: Les lettres qu'elle aura écrites (“the letters that she will have written”). Here que represents the feminine plural noun les lettres and comes before aura écrites. This is mainly visible in writing because many agreement endings are silent.

Pronominal verbs use être, but their agreement can depend on the function of the reflexive pronoun. The basic, high-value pattern is subject agreement: Elle se sera trompée; ils se seront levés. More complex cases appear under Advanced Use below.

Negatives and object pronouns

In a negative sentence, ne ... pas surrounds the conjugated auxiliary:

• Je n'aurai pas terminé. — I will not have finished.
• Ils ne seront jamais partis à temps. — They will never have left on time.

Object pronouns come before the auxiliary:

• Je l'aurai envoyé avant lundi. — I will have sent it before Monday.
• Nous nous serons parlé d'ici là. — We will have spoken to each other by then.

Sequencing future events

The tense is especially common with quand (when), lorsque (when), dès que (as soon as), après que (after), une fois que (once), avant (before) and d'ici (by).

French normally uses a future tense after quand and similar time conjunctions when the reference is future. English normally uses a present form there:

• Quand tu arriveras, j'aurai fini. — When you arrive, I will have finished.
• Dès qu'elle aura reçu la réponse, elle nous appellera. — As soon as she has received the answer, she will call us.

In the second example, the future perfect is inside the time clause because receiving the answer must be complete before the call.

Examples in Context

French	English	Note
J'aurai fini avant midi.	I will have finished before noon.	Completion before a deadline
Quand tu arriveras, je serai parti.	When you arrive, I will have left.	One future action precedes another
D'ici vendredi, nous aurons signé le contrat.	By Friday, we will have signed the contract.	D'ici sets the endpoint
Dès qu'elle aura préparé le dossier, elle vous l'enverra.	As soon as she has prepared the file, she will send it to you.	Completed action in a time clause
Une fois que vous aurez goûté ce fromage, vous comprendrez.	Once you have tasted this cheese, you will understand.	Future perfect before a future result
Ils seront rentrés avant la tombée de la nuit.	They will have returned before nightfall.	Rentrer takes être here
À la fin du mois, elle se sera installée à Lyon.	By the end of the month, she will have settled in Lyon.	Pronominal verb and feminine agreement
Je ne l'aurai pas lu avant demain.	I will not have read it before tomorrow.	Pronoun before the auxiliary; negative around it
Les travaux auront été terminés avant l'ouverture.	The work will have been completed before the opening.	Future perfect passive
Il n'est pas là : il aura oublié notre rendez-vous.	He isn't here: he must have forgotten our appointment.	Deduction about the past
Elle se sera trompée de numéro.	She must have dialled the wrong number.	Probable explanation
Vous aurez sans doute déjà entendu cette histoire.	You have probably already heard this story.	Polite or cautious assumption

Common Mistakes

Using the infinitive instead of the participle

• Wrong: J'aurai finir avant midi.
• Right: J'aurai fini avant midi.
• Why: The auxiliary is followed by a past participle, not an infinitive: fini, not finir.

Choosing the wrong auxiliary

• Wrong: Elle aura partie avant nous.
• Right: Elle sera partie avant nous.
• Why: Partir used without a direct object takes être. The feminine subject also requires partie.

Copying English tense choice after “when”

• Wrong: Quand tu arrives demain, j'aurai fini.
• Right: Quand tu arriveras demain, j'aurai fini.
• Why: For a genuinely future event, French normally uses the future after quand, whereas English says “when you arrive,” not “when you will arrive.”

Putting the future perfect on the later action

• Wrong: Dès qu'elle recevra la réponse, elle nous aura appelés.
• Right: Dès qu'elle aura reçu la réponse, elle nous appellera.
• Why: The future perfect marks the action completed first: she receives the answer, then calls.

Forgetting agreement with être

• Wrong: Elles seront arrivé avant neuf heures.
• Right: Elles seront arrivées avant neuf heures.
• Why: With être, the participle normally agrees with the subject; feminine plural adds -es.

Translating every form as “will have”

• Awkward: Il aura raté le train → “He will have missed the train” in every context.
• Natural in a past deduction: “He must have missed the train” or “He probably missed the train.”
• Why: The French tense can express probability about a past event, not only future completion.

Usage Notes

The future-completion use works in everyday speech and writing, especially when a deadline or sequence matters. In casual conversation, speakers may choose a simpler construction if the order is already obvious: Quand j'ai fini, je t'appelle is common conversational phrasing for “When I'm done, I'll call you,” though careful future sequencing gives Quand j'aurai fini, je t'appellerai. The latter explicitly presents finishing as completed before calling.

The probability use often appears with clues such as sans doute (probably), probablement or déjà, or with a present situation needing an explanation: La lumière est éteinte; ils seront partis (“The light is off; they must have left”). Without context, a sentence such as Il aura terminé can be ambiguous between “He will have finished” and “He must have finished.”

English speakers should pay particular attention to time clauses. English avoids will after “when,” “as soon as” and “once,” but French does not follow that rule. Compare Dès que tu auras décidé... with “As soon as you have decided...”. The French future perfect is not an unnecessary extra future: it shows that the decision is complete before what follows.

Beyond the Basics / Advanced Use

Probability, journalism and cautious inference

The inferential futur antérieur lets a speaker present a past explanation as probable rather than directly verified. It can sound like a reasoned conclusion:

• La porte est ouverte : quelqu'un aura oublié de la fermer. — The door is open; someone must have forgotten to close it.
• Ce changement aura surpris beaucoup de lecteurs. — This change will probably have surprised many readers.

This use occurs in conversation, but it is also useful in journalism, historical commentary and formal prose. Depending on tone, English may use “must have,” “probably,” “presumably,” or “will have.” Do not confuse it with the conditional perfect, which can mark an unconfirmed reported claim: Il aurait démissionné (“He has reportedly resigned”). The future perfect more often presents the speaker's inference.

Agreement with pronominal verbs

The simple rule “pronominal verb equals agreement with the subject” covers forms such as elle se sera levée and elles se seront trompées. At a more advanced level, agreement depends on whether se is a direct or indirect object:

• Elles se seront vues. — They will have seen each other. (se is direct, so vues agrees.)
• Elles se seront parlé. — They will have spoken to each other. (parler à quelqu'un makes se indirect, so no agreement.)
• Elles se seront lavé les mains. — They will have washed their hands. The direct object les mains follows the verb, so lavé does not agree.

These are not special future-perfect rules; they are the general agreement rules for compound tenses.

The passive future perfect

To say that something will have been done, use future avoir + été + the passive participle:

Le rapport aura été publié avant la réunion.

Here aura is the auxiliary of the compound tense, été is the participle of être, and publié agrees with the passive subject le rapport. In Les lettres auront été envoyées, envoyées is feminine plural.

Past viewpoint in reported or narrative contexts

The futur antérieur is anchored to the speaker's present. When a sequence is viewed from a point in the past, French generally uses the conditional perfect instead: Il a promis qu'il aurait terminé avant midi (“He promised that he would have finished before noon”). Keeping this viewpoint distinction clear prevents overusing the future perfect in reported speech.

Practice Tips

1. Build pairs on a timeline. Write two future actions, identify which finishes first, and put that one in the future perfect: Elle aura mangé → elle sortira. Then connect them with quand, dès que or une fois que.
2. Recycle your compound-tense knowledge. Take ten passé composé forms and replace the present auxiliary with its simple-future form: elle est partie → elle sera partie; nous avons compris → nous aurons compris. Check auxiliary choice and agreement each time.
3. Separate the two meanings. For each short sentence such as Il aura oublié, invent one future context and one deduction context. Translate naturally rather than forcing “will have” into both.

Related Concepts

• Prerequisite: Simple Future — supplies the future forms aurai, auras, aura... and serai, seras, sera... used as auxiliaries here.