The Auxiliaries: avoir, être, and the periphrastic aller

A French compound tense is built from two pieces: an auxiliary verb (a conjugated form of avoir or être) and the past participle of the main verb. J'ai mangé (I ate / I have eaten) puts conjugated avoir in front of mangé, the past participle of manger. Je suis arrivé (I arrived / I have arrived) does the same job with être + arrivé. Picking the right auxiliary is one of the most consequential decisions in French past-tense grammar, because it determines not only the form of the verb but also how the participle agrees.

This page lays out the three auxiliaries — avoir, être, and the periphrastic aller (used for the futur proche) — and explains which verbs go with which. It also previews the participle-agreement rules that fall out of the choice. Each rule has its own dedicated page; this is the overview.

avoir: the default auxiliary

The vast majority of French verbs form their compound tenses with avoir + past participle. Every transitive verb, every intransitive verb that isn't on the special list below, and all impersonal/weather verbs use avoir.

The pattern is the same across all compound tenses — only the form of avoir changes:

If you've memorized the conjugation of avoir in any tense, you can build that compound tense for any avoir-verb in the language.

être: the closed list

A small but important set of verbs uses être instead. They fall into two groups:

1. The maison d'être — about seventeen verbs of motion and change of state.
2. All pronominal (reflexive) verbs.

There is nothing else. Every non-reflexive verb that isn't on the maison d'être list takes avoir.

The maison d'être

The traditional list, often taught with the DR & MRS VANDERTRAMP mnemonic:

Plus passer in its intransitive sense ("to drop by, pass through") and the more literary apparaître ("to appear"). All of these verbs share a property: they are intransitive and describe either motion or a change of state. That's the unifying logic — see the transitive-intransitive page for the deeper explanation.

All pronominal verbs

Every verb used reflexively or reciprocally — every verb with me, te, se, nous, vous, se — takes être in compound tenses. There are no exceptions to this. This is why pronominal verbs feel so different from their non-pronominal counterparts: laver takes avoir (j'ai lavé la voiture), but se laver takes être (je me suis lavé).

The pronominal verbs alone make up a huge portion of être-auxiliary usage. Combined with the maison d'être, être easily accounts for a third of compound-tense verb forms in everyday French.

The auxiliary swap: same verb, different meaning

Six maison-d'être verbs can also be used transitively, and in that case they take avoir, not être. The transitive use changes the meaning, and the participle-agreement rules switch with it. The verbs are monter, descendre, sortir, entrer, retourner, passer, plus to a lesser extent rentrer.

The test is simple: if there's a direct object after the verb, you're using it transitively, and you need avoir. The full inventory of these verbs and their meaning shifts is treated in the transitive-intransitive page.

Past participle agreement: the consequence

The auxiliary you choose decides how the past participle behaves.

With être: agree with the subject

The participle agrees in gender and number with the subject, exactly like an adjective. So masculine singular gets the bare form, feminine singular adds -e, masculine plural adds -s, feminine plural adds -es:

This is intuitive: with être, the participle is functionally an adjective describing the state of the subject ("she is gone," "they are arrived"), and adjectives in French agree with what they describe.

With avoir: agree with a preceding direct object — never with the subject

The default behavior with avoir is no agreement. The participle stays in its base form regardless of the subject:

But if the direct object precedes the verb — through pronoun replacement, a relative clause with que, or fronted question word quel(le)(s) — the participle agrees with that direct object:

The agreement is mostly orthographic — most participle agreement is silent — but it matters in writing. For a small set of participles ending in a consonant (pris, mis, fait, dit, écrit, ouvert), the agreement is audible: les lettres que j'ai écrites sounds different from j'ai écrit les lettres.

This is one of the rules French speakers themselves struggle with, and it has its own dedicated page; see agreement with avoir.

With pronominal verbs: usually agree with the subject — but the rule is more delicate

Pronominal verbs use être, so a learner's first guess is to agree with the subject — and that works most of the time:

But the deeper rule is that pronominal participles agree with a preceding direct object, just like with avoir — except that the reflexive pronoun usually is the direct object, which is why subject-agreement works in most cases. When the reflexive is an indirect object, agreement disappears:

This is one of the most tested points in French dictation, and it is treated in detail in agreement with être.

Modal verbs always take avoir

Modal verbs — vouloir, pouvoir, devoir, savoir, falloir — all take avoir as their auxiliary, even when they govern an embedded verb that would normally take être:

The auxiliary is selected by the modal itself, not by the embedded verb. The participle of the modal does not agree with anything (no direct object precedes it in these structures).

The third "auxiliary": aller + infinitive

French has a third quasi-auxiliary that doesn't form compound tenses but does form a periphrastic future, the futur proche: conjugated aller + infinitive of the main verb.

The futur proche is the standard way to express the near future in conversational French. It overlaps heavily with the futur simple but is more colloquial. The construction is finite + infinitive, not auxiliary + participle, so the agreement rules from avoir/être don't apply at all. It's a different structure that just happens to perform a similar job.

A parallel structure is the passé récent with venir de + infinitive ("to have just done"):

And the present-progressive emphasis with être en train de + infinitive ("to be in the middle of doing"):

These three constructions — aller + inf., venir de + inf., être en train de + inf. — are the three main aspectual periphrases of French. They are not strictly auxiliaries in the textbook sense, but they cover the work that English does with helping verbs (will, just, be -ing).

Comparison with English

English uses one auxiliary, have, for all perfect tenses regardless of transitivity (I have gone, I have eaten, I have seen). The verb be + past participle exists too, but it forms the passive voice ("the door was closed by the wind"), not the perfect — and English speakers feel that distinction sharply. So the French use of être in je suis arrivé is genuinely confusing on first encounter: it looks passive ("I am arrived") but is actually active.

The historical explanation is real: at an earlier stage of Romance languages, intransitive verbs of motion and change really were treated as quasi-passives (the subject undergoes the arriving). Modern French has lost the intuition but kept the form. Italian and Dutch still preserve the same dual-auxiliary system; Spanish and Portuguese have collapsed everything to haber/ter; English collapsed everything to have.

The other point of friction is that English speakers often translate the futur proche as a literal "going to." That works, but learners then over-extend aller to mean "to be about to," which it isn't. Je vais partir says you intend to leave soon; je vais à Paris says you are physically going to Paris. Watch for the infinitive that follows: with infinitive, it's the futur proche; with a noun or location, it's the regular motion verb.

Common Mistakes

Key takeaways

• Avoir is the default auxiliary. Use it unless the verb is on the maison d'être list or is pronominal.
• The maison d'être contains about seventeen intransitive verbs of motion and change of state (DR & MRS VANDERTRAMP).
• All pronominal verbs use être. No exceptions.
• Six pivot verbs (monter, descendre, sortir, entrer, retourner, passer) switch to avoir when used transitively.
• Modal verbs always take avoir, regardless of what the embedded verb takes.
• With être, the participle agrees with the subject. With avoir, the participle agrees only with a preceding direct object.
• Aller + infinitive (futur proche), venir de + infinitive (passé récent), and être en train de + infinitive (progressive) are the three main aspectual periphrases — not auxiliaries proper, but functionally similar.