Avoir is the default auxiliary in the passé composé. Être is a short closed list, mostly verbs of the subject's own movement or change of state, plus every pronominal verb. Here is the mechanism behind the list, the mixed verbs that switch, the agreement rules, and how to practice the choice out loud.
- ✓The decision rule in one line: avoir is the default, and être is a short closed list, mostly verbs of the subject's own movement or change of state, plus every pronominal verb.
- ✓Every pronominal verb takes être. That rule alone covers a huge share of the choices you actually face.
- ✓A small set of movement verbs switch to avoir when they take a direct object: je suis monté but j'ai monté les valises.
- ✓Under être the participle agrees with the subject. Under avoir it agrees with a direct object placed before the verb, and never with the subject.
- ✓Knowing the rule and producing the right auxiliary under time pressure are different skills. Speaking practice is what closes that gap.
A quick note on who is writing this. I am building Coucou, an AI French tutor, and I am also the learner it was built for. My wife is French, which means my French gets tested at the family table, and I have the honest scars to show for it. I gave myself a personal goal of roughly B2 by the end of 2026. Right now, around Day 97, my roadmap says B1 with 67 milestones tracked and 66 functional. The first milestone on the whole tracker just locked: passé composé avec avoir, after two clean days in a row. The honest summary of where I am is that the midday fixes, enfant without the article and dehors, are consolidating from memory, but the imparfait versus conditionnel choice, jouais or jouerais, is newly shaky. The auxiliary choice this page is about is still at the top of my weak list: avions still wants to become avaient under pressure. I am not fluent. This page is the wall I am standing at, and the examples below are the ones I actually practice.
The decision rule in one sentence
The rule is short. Avoir is the default: most French verbs take avoir in the passé composé, j'ai dormi, j'ai mangé, j'ai parlé. Être is the exception, a short closed list, and almost everything on it is about the subject's own movement or change of state. Plus every pronominal verb takes être. That is the whole system.
Two examples make it visible. Je suis allé au marché: aller is on the short list, a verb of the subject's own movement, so the auxiliary is être. J'ai mangé une pomme: manger is a normal verb, and normal verbs take avoir by default.
The mechanism matters more than the list, because the list is mostly verbs where the subject is the one who moves or changes. Aller, venir, arriver, partir, naître, mourir, tomber: what happened to the subject, so être. Manger, parler, acheter, écrire: normal verbs, so avoir. The mechanism explains the list, but you still learn the list itself. Avoir is where you start, and être is the short family you check for.
The maison d'être: the verbs that take être
The classic list is called the maison d'être, and it is usually taught as sixteen verbs to memorize, the set the Dr Mrs Vandertramp mnemonic names: devenir, revenir, monter, rester, sortir, venir, aller, naître, descendre, entrer, rentrer, tomber, retourner, arriver, mourir, and partir. Passer is often tacked on as a seventeenth, but it behaves like the mixed verbs below, so I keep it there. The reflexive form of every verb also takes être, which is a separate rule and a big one, covered in the next section.
The mechanism under the list is simpler than the list itself. Almost every verb on it describes the subject's own movement or change of state: the subject moves, arrives, leaves, is born, dies, falls, stays. The sentence is about what happened to the subject rather than about something done to an object, and that is why être carries the tense and the participle agrees with the subject. The mechanism does not replace the list, it explains it, and the sixteen stop feeling like a random grab bag once you see the family.
Elle est née à Lyon. Nous sommes partis à huit heures. Ils sont tombés dans l'escalier. The participle takes the gender and number of the subject in every one of these.
Pronominal verbs: the rule with no exceptions
Every pronominal verb takes être in the passé composé. Se lever, se coucher, se souvenir, se promener, se dépêcher, all of them, with no exceptions.
Je me suis levé à sept heures. Elle s'est dépêchée. Nous nous sommes souvenus de ce jour-là. In the common case the reflexive pronoun is the direct object, and the participle agrees with the subject, so the ending changes with the person speaking. Two corners to know: when se is indirect, ils se sont parlé, and when a direct object follows the verb, elle s'est lavé les mains, the participle stays invariable.
This is the most reliable shortcut in the whole system, and it is the one that caught me live. On August 13 my tutor asked about my morning routine and I wrote je me suis levé when the sentence needed the present tense, je me lève à sept heures. The reflexive passé composé was correct as a form, but the tense was wrong for a daily habit. One receipt, two lessons: pronominal verbs take être, and choosing the auxiliary is only half the decision, the tense still has to be right.
The mixed verbs: when the auxiliary switches
A small set of movement verbs take être when they describe the subject's movement, and switch to avoir when they take a direct object. The common ones are monter, descendre, sortir, entrer, retourner, and passer.
Je suis monté au deuxième étage. I moved myself up, so être. J'ai monté les valises. There is a direct object, the suitcases, so avoir.
Elle est sortie à vingt heures. Elle a sorti les poubelles. Je suis descendu à la cave. J'ai descendu les bagages. Same verbs, same person, different auxiliary, and the meaning of the sentence changes with the switch.
This is the part of the system where most learners freeze, and the honest fix is to drill the pairs out loud until the switch becomes automatic. Je suis monté, j'ai monté les valises. Je suis sorti, j'ai sorti les poubelles. The contrast is doing the teaching.
The agreement rules
Under être, the past participle agrees with the subject. Elle est sortie, elles sont parties, je me suis levé. The participle is an adjective describing the subject, so it takes the subject's gender and number. The pronominal corner from the section above is the exception: when the reflexive pronoun is indirect, ils se sont parlé, or when a direct object follows the verb, elle s'est lavé les mains, the participle stays invariable.
Under avoir, the participle does not agree with the subject. J'ai mangé is correct, j'ai mangée is wrong, no matter who is speaking or how many people are eating. The subject never drives the agreement under avoir.
The one exception: the participle agrees with a direct object that comes before the verb. La lettre que j'ai écrite, les valises que j'ai montées, les pommes que j'ai mangées. The object came before the verb, so the participle matches it. This is the rule that trips people at the exam table, and it is also the rule you can skip for most everyday speaking, because most spoken sentences place the object after the verb.
Why knowing the rule is not enough
The honest part is where the auxiliary gets decided. It happens in the split second before the participle comes out, and no written exercise simulates that. Fill-in-the-blank drills put être and avoir on the page and ask you to pick. Speaking asks you to already be holding the right one while the sentence is still forming, under time pressure, with someone listening.
My own tracker makes the gap concrete. The passé composé avec avoir milestone just locked after two clean days, and my tracker's weak list still carries the avoir-paradigm and imparfait cluster at the top: avions turning into avaient even with the paradigm on screen, the -ger endings like voyageaient, and the plus-que-parfait auxiliary, j'avais mangé, still shaky. The knowledge is there. The production wobbles.
The practice loop that actually moves this is speaking and getting told which piece slipped. The reflexive mix-up on August 13 came out in free conversation, because that is where the auxiliary choice actually gets made, in the middle of a real sentence. Recording yourself catches some of it, and a second set of ears catches more, which is the honest seam where the tool I am building fits. Coucou, the AI French tutor I am building, texts you when it is time to practice, so the production reps happen daily. It scores your pronunciation per word, names the word that was off, and sends native model audio back. It spaces out your mistakes so the same slip resurfaces until you fix it, and when a new grammar concept comes up, it states the defining rule first, then drills the form, the same order this page uses. Free conversation counts toward your progress too, which is how the reflexive tense mix-up from August 13 surfaced.
The honest limits are real. A few tools now score pronunciation, mostly on drilled or copied lines, Copycat on copied phrases and Conversaflex on phoneme drills, so Coucou is not the only scorer in the field. Its scoring is good but not flawless, and it can misread fast or noisy audio. It is not a replacement for a human teacher, and it does not promise fluency. It is free while early access lasts, and I approve new people by hand, usually within a few hours. The bigger point is the mechanic, not any single tool: auxiliary choice is a production skill, and production skills need daily output plus feedback.
How to practice choosing the auxiliary
A ten minute routine that targets exactly this wall. First, narrate your morning out loud and sort every verb by whether it belongs to the être family. The short-list verbs take être: je me suis levé, je suis sorti, je suis allé au marché. The rest take avoir: j'ai pris un café, j'ai acheté du pain, j'ai écrit un message.
Second, drill the mixed verbs in pairs until the switch becomes automatic. Je suis monté, j'ai monté les valises. Elle est sortie, elle a sorti les poubelles. Je suis descendu, j'ai descendu les bagages.
Third, record the whole thing and listen for where you hesitated between the auxiliaries, because hesitation is the slip happening in slow motion. If you want the tense choice on top of it, the guide to passé composé vs imparfait covers when the auxiliary question even comes up, and the article on getting unstuck at intermediate level explains why grammar knowledge and speaking ability diverge in the first place. If your block is that you understand French but freeze when producing it, the flagship article on that exact problem is where the whole story starts, and the page on AI pronunciation scoring explains what a scored check can and cannot do.
That is the whole page. Avoir is the default. Être is the short family: the subject's own movement or change of state, plus every pronominal verb. And the choice is a production skill, so the reps matter more than the chart. Say it out loud until your mouth knows the list.
Last updated: 17 August 2026. This is a personal account from someone still learning, not expert linguistic advice. French examples reflect standard usage, and spoken French bends rules in ways textbooks do not.
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