French grammar · Advanced

French Conditional Perfect Conjugations: J'aurais Fait and What It Carries

The conditional perfect, le conditionnel passé, puts avoir or être into the conditional and adds a past participle: j'aurais fini, je serais parti. It says what would have happened, and it is the tense French uses for regret about the past.

J'aurais dû t'écouter.

I should have listened to you.

What it is

Once you can conjugate avoir and être in the conditional, this tense is finished: aurais, aurais, aurait, aurions, auriez, auraient, or serais, serais, serait, serions, seriez, seraient, plus the participle. What takes longer to absorb is how much emotional weight French loads onto it.

Si j'avais su, je ne serais pas venu. — If I'd known, I wouldn't have come.

How to spot it

Two words, the first of which is a conditional form of avoir or être. If the auxiliary carries -rais, -rait or -raient and a participle follows, you're in the conditional perfect.

  • Tu aurais pu me le dire. — You could have told me.
  • Elle serait partie plus tôt. — She would have left earlier.
  • Nous aurions préféré rester. — We would have preferred to stay.
  • Ils se seraient trompés de date. — They must have got the date wrong.

Compare j'aurais fait, I would have done, with j'aurai fait, I will have done. A single s separates a regret from a deadline.

Conditional Perfect Conjugations Quick Reference

The two auxiliaries, and what changes with each

AuxiliaryExampleAgreementEnglish
avoirj'aurais fininone with the subjectI would have finished
avoir + preceding objectles lettres que j'aurais écriteswith the objectthe letters I would have written
être, movement verbelle serait partiewith the subjectshe would have left
être, plural subjectils seraient venuswith the subjectthey would have come
être, reflexiveje me serais levé(e)with the subjectI would have got up
avoir, modaltu aurais dûnoneyou should have

Common Conditional Perfect Conjugations Examples in French

Where the conditional perfect earns its keep:

Regret

J'aurais dû réserver plus tôt.
I should have booked earlier.
On aurait mieux fait de partir hier.
We'd have done better to leave yesterday.
J'aurais aimé le connaître.
I'd have liked to know him.
Elle aurait voulu être là.
She would have liked to be there.

J'aurais dû is the standard French for I should have, and it accounts for a large share of all conditional perfects.

Reproach

Tu aurais pu prévenir !
You could have said something!
Vous auriez dû nous attendre.
You should have waited for us.
Il aurait pu faire un effort.
He could have made an effort.
Ils n'auraient pas dû accepter.
They shouldn't have accepted.

The difference between regret and reproach is only the subject. The grammar is identical.

Unrealised Conditions

Si tu m'avais appelé, je serais venu.
If you'd called me, I'd have come.
Sans ton aide, j'aurais échoué.
Without your help, I'd have failed.
Avec un peu de chance, on aurait gagné.
With a bit of luck, we'd have won.
À ta place, j'aurais refusé.
In your position, I'd have refused.

The condition is often left out and implied by sans, avec or à ta place rather than spelled out with si.

Unverified Reports

Le voleur se serait enfui par le toit.
The thief reportedly escaped over the roof.
Deux personnes auraient été blessées.
Two people are said to have been injured.
L'incendie aurait démarré dans la cuisine.
The fire allegedly started in the kitchen.
Il aurait démissionné hier soir.
He is reported to have resigned last night.

French news reports use this tense where English inserts reportedly or allegedly. Nothing hypothetical is meant.

Building the Forms

The construction is mechanical; the agreement rules are the ordinary compound-tense rules.

The Conditional Sits on the Auxiliary

The participle never changes for tense or mood. All the grammatical work happens in avoir or être, which is why the same participle appears in j'ai fini, j'aurai fini and j'aurais fini.

Nous aurions terminé avant midi.

We'd have finished before noon.

Conditional auxiliary + participle.

Auxiliary Choice Is Unchanged

Whatever auxiliary the verb takes in the passé composé, it takes here. Verbs of movement and change of state, plus all reflexives, use être; everything else uses avoir.

Elle serait rentrée avant la nuit.

She'd have got home before dark.

Same auxiliary as the passé composé.

Être Participles Agree With the Subject

Because être is involved, the participle behaves like an adjective: serait partie, seraient partis, se serait levée. This is the single most common written error in the tense.

Elles seraient venues avec nous.

They'd have come with us.

être → agreement with the subject.

Negation Wraps the Auxiliary

Ne … pas brackets the conditional form of avoir or être, leaving the participle outside. Object pronouns go in front of the whole group.

Je ne l'aurais pas cru.

I wouldn't have believed it.

ne + pronoun + auxiliary + pas + participle.

The Modals Take an Infinitive After the Participle

Devoir, pouvoir and vouloir keep their infinitive when they go into this tense, producing a three-verb sequence: aurais dû partir, aurais pu venir, aurais voulu savoir.

Tu aurais pu me téléphoner.

You could have phoned me.

aurais + dû / pu / voulu + infinitive.

Common Mistakes with Conditional Perfect Conjugations

Incorrect: Si j'aurais su, je ne serais pas venu. — If I'd known, I wouldn't have come.

Correct: Si j'avais su, je ne serais pas venu. — If I'd known, I wouldn't have come.

Si never takes a conditional. The unrealised condition goes into the plus-que-parfait, and the conditional perfect belongs in the other clause. This is the best-known grammatical error in French.

Incorrect: Elle serait parti sans nous. — She'd have left without us.

Correct: Elle serait partie sans nous. — She'd have left without us.

With être the participle agrees with the subject, and elle needs an e. Learners often carry over the no-agreement habit of avoir compounds.

Incorrect: J'aurais du te prévenir. — I should have warned you.

Correct: J'aurais dû te prévenir. — I should have warned you.

The participle of devoir carries a circumflex in the masculine singular, which is what distinguishes dû from the article du. Without it the sentence reads as I would have some of.

Incorrect: Tu aurais pu de me le dire. — You could have told me.

Correct: Tu aurais pu me le dire. — You could have told me.

Pouvoir, devoir and vouloir take a bare infinitive with no preposition, in every tense. The object pronouns attach to that infinitive, not to the auxiliary.

The Full Paradigms

Three tables: verbs with avoir, verbs with être including reflexives, and the three modal verbs that carry most of the tense's emotional weight.

Verbs Taking Avoir

No agreement with the subject. The participle stays in its base form whoever the subject is.

Pronounavoir (conditionnel)+ finir+ dire
je / j'auraisj'aurais finij'aurais dit
tuauraistu aurais finitu aurais dit
il / elle / onauraitil aurait finielle aurait dit
nousaurionsnous aurions fininous aurions dit
vousauriezvous auriez finivous auriez dit
ils / ellesauraientils auraient finielles auraient dit

Aurait and auraient are pronounced identically. Only the spelling tells you whether the subject is singular or plural.

Verbs Taking Être, and Reflexives

Here the participle agrees with the subject. The bracketed endings show what a feminine or plural subject adds.

Pronounêtre (conditionnel)+ partir+ se lever
jeseraisje serais parti(e)je me serais levé(e)
tuseraistu serais parti(e)tu te serais levé(e)
il / elle / onseraitelle serait partieil se serait levé
nousserionsnous serions partisnous nous serions levés
vousseriezvous seriez partisvous vous seriez levés
ils / ellesseraientelles seraient partiesils se seraient levés

In a reflexive, the pronoun goes before the auxiliary and never between the two verbs: je me serais levé, not je serais me levé.

The Three Verbs of Regret

Devoir, pouvoir and vouloir in this tense translate as should have, could have and would have liked to. All three take avoir and all three are followed by an infinitive.

Pronoundevoirpouvoirvouloir
j'j'aurais dûj'aurais puj'aurais voulu
tutu aurais dûtu aurais putu aurais voulu
il / elle / onil aurait dûil aurait puil aurait voulu
nousnous aurions dûnous aurions punous aurions voulu
vousvous auriez dûvous auriez puvous auriez voulu
ils / ellesils auraient dûils auraient puils auraient voulu

Dû takes a circumflex to distinguish it from the article du. The feminine and plural forms lose it: due, dus, dues.

The Three Things This Tense Is For

Beyond translating would have, the conditional perfect has two jobs that have nothing to do with hypotheses.

Si plus the pluperfect

For a condition that was never met, French pairs si plus the plus-que-parfait with a conditional perfect in the other clause. Both halves refer to a past that didn't happen.

Si j'avais su, je serais resté chez moi.
If I'd known, I'd have stayed at home.
S'il avait fait beau, on aurait pique-niqué.
If the weather had been good, we'd have had a picnic.
Je t'aurais aidé si tu me l'avais demandé.
I'd have helped you if you'd asked me.

Never put a conditional after si. The si clause takes the plus-que-parfait, and the conditional perfect goes in the other half.

Should have and could have

English builds these with a modal plus have; French builds them by putting the modal itself into the conditional perfect. The infinitive that follows carries the action.

Tu aurais dû me le dire.
You should have told me.
J'aurais pu t'accompagner.
I could have gone with you.
Il aurait mieux valu attendre.
It would have been better to wait.

Il aurait mieux valu is the impersonal version, built on valoir, and it's a useful way to voice regret without blaming anyone.

Reporting something you can't confirm

Journalists put a past event into the conditional perfect to signal that the information is second-hand. The tense replaces an English adverb.

Le suspect aurait quitté le pays.
The suspect has reportedly left the country.
L'accord aurait été signé mardi.
The agreement was apparently signed on Tuesday.
Elle se serait installée à Lyon.
She is said to have moved to Lyon.

In this use the sentence has no if clause, spoken or implied, which is how you know it isn't hypothetical.

Conditional Perfect Conjugations FAQs

How do you form the conditional perfect in French?
Put avoir or être into the conditional and add the past participle: j'aurais parlé, tu aurais fini, elle serait partie, nous nous serions levés. The auxiliary is the same one the verb takes in the passé composé.
What does j'aurais dû mean?
I should have. It's the conditional perfect of devoir, followed by an infinitive: j'aurais dû partir plus tôt, I should have left earlier. Its two companions are j'aurais pu, I could have, and j'aurais voulu, I would have liked to.
What tense goes after si with the conditional perfect?
The plus-que-parfait: si tu m'avais prévenu, je serais venu. A conditional form of any kind after si is an error, however natural it feels in English.
What's the difference between j'aurai fait and j'aurais fait?
J'aurai fait is the future perfect, I will have done, used for deadlines: demain, j'aurai fini. J'aurais fait is the conditional perfect, I would have done. One s changes a plan into a regret.
Why do French news reports use this tense?
To mark information as unconfirmed. Le suspect aurait pris la fuite means the suspect reportedly fled: the journalist is passing on a claim rather than asserting a fact, and the conditional does the work English does with allegedly.