The future subjunctive is built on one of the neatest morphological recipes in the Portuguese verb system. There is a single formation rule that covers every regular verb in the language, and it is learnable in about thirty seconds. Once you have it, you can produce the future subjunctive of any -ar, -er, or -ir verb you encounter, without memorising separate paradigms. This page walks through the rule, presents the full paradigms for each verb class, and then takes a careful look at a remarkable feature: for regular verbs, the singular future subjunctive forms are homographs with the impersonal infinitive. Falar looks identical whether it is "to speak" (infinitive) or "I / he / she / you speak" (future subjunctive). That coincidence is not a flaw — it is a deep, elegant feature of Portuguese grammar.
The formation rule
Take the 3rd person plural of the preterite — the eles / elas / vocês form. Drop the final -am. What remains is the future subjunctive stem. Add the endings: -, -es, -, -mos, -em.
| Step | Action | Example (falar) |
|---|---|---|
| 1 | Start with 3pl preterite | falaram |
| 2 | Drop -am | falar- |
| 3 | Add endings (-, -es, -, -mos, -em) | falar / falares / falar / falarmos / falarem |
-ar verbs: falar (to speak)
3pl preterite: falaram → stem falar-.
| Subject | Future Subjunctive | Notes |
|---|---|---|
| eu | falar | identical to infinitive |
| tu | falares | — |
| ele / ela / você | falar | identical to infinitive |
| nós | falarmos | identical to personal infinitive |
| eles / elas / vocês | falarem | identical to personal infinitive |
Se falares com o João, pede-lhe que me ligue.
If you speak to João, ask him to call me.
Quando falarmos com a professora, explicamos tudo.
When we talk to the teacher, we'll explain everything.
Sempre que falarem português no trabalho, tenta acompanhar.
Whenever they speak Portuguese at work, try to follow along.
Other common -ar verbs
| Verb | 3pl pret. | eu / ele | tu | nós | eles |
|---|---|---|---|---|---|
| chegar (to arrive) | chegaram | chegar | chegares | chegarmos | chegarem |
| comprar (to buy) | compraram | comprar | comprares | comprarmos | comprarem |
| trabalhar (to work) | trabalharam | trabalhar | trabalhares | trabalharmos | trabalharem |
| estudar (to study) | estudaram | estudar | estudares | estudarmos | estudarem |
| jogar (to play) | jogaram | jogar | jogares | jogarmos | jogarem |
| gostar (to like) | gostaram | gostar | gostares | gostarmos | gostarem |
Assim que chegares, manda mensagem.
As soon as you arrive, send a message.
Se comprares pão, compra também leite.
If you buy bread, buy milk too.
Quando estudarmos juntos, vamos combinar um sítio.
When we study together, we'll agree on a place.
-er verbs: comer (to eat)
3pl preterite: comeram → stem comer-.
| Subject | Future Subjunctive |
|---|---|
| eu | comer |
| tu | comeres |
| ele / ela / você | comer |
| nós | comermos |
| eles / elas / vocês | comerem |
Se comeres tudo, podes ter sobremesa.
If you eat everything, you can have dessert.
Depois de comermos, vamos dar uma volta.
After we eat, we'll go for a walk.
Quando os miúdos comerem, damos-lhes banho.
When the kids have eaten, we'll bath them.
Other common -er verbs
| Verb | 3pl pret. | eu / ele | tu | nós | eles |
|---|---|---|---|---|---|
| beber (to drink) | beberam | beber | beberes | bebermos | beberem |
| viver (to live) | viveram | viver | viveres | vivermos | viverem |
| aprender (to learn) | aprenderam | aprender | aprenderes | aprendermos | aprenderem |
| correr (to run) | correram | correr | correres | corrermos | correrem |
| vender (to sell) | venderam | vender | venderes | vendermos | venderem |
Enquanto viveres aqui, tens a minha ajuda.
As long as you live here, you have my help.
Se aprenderes a tocar guitarra, ensina-me.
If you learn to play guitar, teach me.
-ir verbs: partir (to leave)
3pl preterite: partiram → stem partir-.
| Subject | Future Subjunctive |
|---|---|
| eu | partir |
| tu | partires |
| ele / ela / você | partir |
| nós | partirmos |
| eles / elas / vocês | partirem |
Se partires cedo, evitas o trânsito.
If you leave early, you'll avoid traffic.
Quando partirmos, não esqueçam as malas.
When we leave, don't forget the suitcases.
Other common -ir verbs
| Verb | 3pl pret. | eu / ele | tu | nós | eles |
|---|---|---|---|---|---|
| abrir (to open) | abriram | abrir | abrires | abrirmos | abrirem |
| decidir (to decide) | decidiram | decidir | decidires | decidirmos | decidirem |
| dormir (to sleep) | dormiram | dormir | dormires | dormirmos | dormirem |
| subir (to go up) | subiram | subir | subires | subirmos | subirem |
| ouvir (to hear) | ouviram | ouvir | ouvires | ouvirmos | ouvirem |
Quando decidirmos, avisamos-vos.
When we decide, we'll let you know.
Se dormires melhor esta noite, vais-te sentir muito melhor.
If you sleep better tonight, you'll feel much better.
Sempre que ouvires esta canção, pensa em mim.
Whenever you hear this song, think of me.
The homograph phenomenon: future subjunctive looks like the infinitive
Here is one of the most elegant — and occasionally confusing — facts about regular Portuguese future subjunctives: the 1sg and 3sg future subjunctive forms are written and pronounced identically to the infinitive. Falar is both "to speak" and "I speak / he speaks / you speak" (future subjunctive). Likewise comer, partir, chegar, viver, abrir, and every regular verb you will ever meet.
This is not a defect of the writing system; it is a direct reflection of the historical origin of the future subjunctive. The tense evolved from the Latin future perfect subjunctive, whose endings happened to fuse with the infinitive stem to produce these specific shapes. Portuguese inherited the whole package.
Compare:
| Form | Meaning | Grammar |
|---|---|---|
| Eu preciso de falar com ela. | I need to speak to her. | falar = infinitive |
| Se eu falar com ela, digo-te. | If I speak to her, I'll tell you. | falar = future subjunctive (eu) |
| Para eu chegar a tempo, tenho de sair já. | For me to arrive on time, I have to leave now. | chegar = personal infinitive (eu) |
| Quando eu chegar, ligo-te. | When I arrive, I'll call you. | chegar = future subjunctive (eu) |
Three identical-looking forms. Three completely different grammatical roles. Context, specifically the conjunction or preposition preceding the verb, tells you which:
- After a preposition (para, de, a, por, sem) → infinitive (personal or impersonal).
- After quando / se / assim que / logo que / enquanto / sempre que / depois que / mal / como / conforme, or after quem / o que / onde as an indefinite relative → future subjunctive.
Para falarmos mais, liga-me amanhã.
So that we can talk more, call me tomorrow. (para + personal infinitive)
Quando falarmos amanhã, combinamos tudo.
When we speak tomorrow, we'll settle everything. (quando + future subjunctive)
The forms are identical: falarmos. But para triggers personal infinitive, and quando triggers future subjunctive. Both are grammatically correct Portuguese, just in different clause types.
Why the homograph matters for -ar verbs specifically
For -ar verbs, the 1sg and 3sg future subjunctive is pronounced exactly like the infinitive, with no vowel change, no stress shift, nothing. Falar and falar sound identical in all contexts.
For -er and -ir verbs the same is true in writing, and pronunciation is identical as well. Comer and comer, partir and partir.
This differs sharply from, say, Spanish — where cuando llegue has a visibly different form from the infinitive llegar. In Portuguese, the "future subjunctive" you hear is often going to look, to the untrained ear, exactly like an infinitive. That is fine. Trust the conjunction.
The plural forms: where the distinction shows
The 2sg (falares), 1pl (falarmos), and 3pl (falarem) future subjunctive forms are not homographs with the impersonal infinitive (which is always falar). They are homographs with the corresponding personal infinitive forms: falares, falarmos, falarem are the personal infinitive endings for tu, nós, and eles.
| Subject | Impersonal inf. | Personal inf. | Future subj. |
|---|---|---|---|
| (invariable) | falar | — | — |
| eu | — | falar | falar |
| tu | — | falares | falares |
| ele / ela / você | — | falar | falar |
| nós | — | falarmos | falarmos |
| eles / elas / vocês | — | falarem | falarem |
So for regular verbs, the personal infinitive and the future subjunctive are identical paradigms, form for form. The only distinction is syntactic: what triggers each.
This is a genuine feature of Portuguese, not a bug. It means you can master two tenses' worth of paradigms by learning one set of endings. It also means when a Portuguese speaker hears or writes quando falarmos, the form carries no stress on being "subjunctive" as opposed to "infinitive" — the distinction simply does not exist at the level of morphology. The trigger word (quando, se, para, por…) is what assigns the grammatical label.
An extended example showing contrast
Para eu chegar a tempo, tenho de sair às sete.
For me to arrive on time, I have to leave at seven. (para + personal infinitive)
Quando eu chegar, ligo-te.
When I arrive, I'll call you. (quando + future subjunctive)
Antes de chegarmos, passamos no supermercado.
Before we arrive, we stop at the supermarket. (antes de + personal infinitive)
Assim que chegarmos, jantamos.
As soon as we arrive, we have dinner. (assim que + future subjunctive)
Same word chegar / chegarmos in all four sentences. Same speaker, same event. The only difference is whether the introducer is a preposition (→ infinitive) or a temporal conjunction (→ future subjunctive). Native speakers do not find this ambiguous; the trigger is unambiguous for them.
Spelling changes: the usual -car, -gar, -çar patterns
Regular verbs whose infinitive ends in -car, -gar, or -çar show a spelling adjustment in the 3pl preterite (-aram keeps the hard consonant: ficaram, chegaram, começaram). Because the future subjunctive is built from this stem, the same spelling carries over:
| Verb | 3pl pret. | Future subj. stem | eu form |
|---|---|---|---|
| ficar (to stay) | ficaram | ficar- | ficar |
| chegar (to arrive) | chegaram | chegar- | chegar |
| começar (to begin) | começaram | começar- | começar |
| explicar (to explain) | explicaram | explicar- | explicar |
| pagar (to pay) | pagaram | pagar- | pagar |
Because the future subjunctive stem ends in r before the ending (no front vowel follows), there are no "soft vs hard consonant" complications — -c- and -g- stay -c- and -g-, and the cedilla of -ç- stays in place.
Se ficares cá esta noite, a cama de cima é tua.
If you stay here tonight, the top bunk is yours.
Quando pagarmos a renda, ainda sobra algum dinheiro.
When we pay the rent, there's still some money left over.
Full comparative table
Here are all three regular verb classes side by side, to let you see the pattern at a glance.
| Subject | falar (-ar) | comer (-er) | partir (-ir) |
|---|---|---|---|
| eu | falar | comer | partir |
| tu | falares | comeres | partires |
| ele / ela / você | falar | comer | partir |
| nós | falarmos | comermos | partirmos |
| eles / elas / vocês | falarem | comerem | partirem |
The pattern is identical across all three classes. The class-characteristic vowel (-a-, -e-, -i-) stays in the stem; the endings are the same (-), -es, (-), -mos, -em.
Why this is one of the most elegant corners of Portuguese grammar
The regular future subjunctive is beautiful because:
- One rule covers every regular verb. There are no subconjugations to memorise — just drop -am, add endings.
- The paradigm is syncretic with the personal infinitive, meaning you learn two paradigms for the price of one.
- The endings are minimal: four distinct suffixes (-, -es, -mos, -em) do the whole job.
- The formation is historical: the future subjunctive descends directly from Latin, and the syncretism with the infinitive reflects a deep morphological truth about the verb stem.
Compare with the indicative future perfect, the pluperfect indicative, and the imperfect subjunctive — all of which have more moving parts. The future subjunctive, despite being one of the most exotic tenses for learners to encounter, is actually one of the simplest to form.
Practising the rule: a walk-through
Take a regular verb you have never consciously conjugated in the future subjunctive — say visitar (to visit):
- 3pl preterite: visitaram.
- Drop -am: visitar-.
- Add endings: visitar, visitares, visitar, visitarmos, visitarem.
And you have the full paradigm. Now use it in a sentence:
Quando visitares Évora, vai ao Templo de Diana.
When you visit Évora, go to the Temple of Diana.
Or pick conhecer (to know, to be acquainted with):
- 3pl preterite: conheceram.
- Drop -am: conhecer-.
- Forms: conhecer, conheceres, conhecer, conhecermos, conhecerem.
Quando conheceres o meu irmão, vais ver que é mesmo assim.
When you meet my brother, you'll see he really is like that.
The rule does all the work. You do not need a cheat sheet for each new verb.
Common Mistakes
❌ Quando eu chego, ligo-te.
Incorrect — present indicative instead of future subjunctive.
✅ Quando eu chegar, ligo-te.
When I arrive, I'll call you.
This is the single highest-yield correction for English-speaking learners. After quando + future event, the future subjunctive is obligatory.
❌ Se comprarei pão, trago leite.
Incorrect — future indicative after *se*.
✅ Se comprar pão, trago leite.
If I buy bread, I'll bring milk.
Portuguese never puts the future indicative after se. Use the future subjunctive.
❌ Assim que acaba, vamos.
Incorrect — present indicative instead of future subjunctive.
✅ Assim que acabar, vamos.
As soon as it's over, we go.
After assim que + future event, future subjunctive. English-influenced present indicative is the commonest slip.
❌ Quando falar com ele amanhã, te direi.
Mixed European/Brazilian orthography and pronoun placement. In EP the pronoun placement matters.
✅ Quando falar com ele amanhã, digo-te.
When I speak with him tomorrow, I'll tell you.
Correct Portuguese future subjunctive, with EP pronoun placement on the main clause verb.
❌ Se tu estudas mais, passas no exame.
Indicative condition — this reads as a general habitual, not a forward-looking realistic conditional.
✅ Se tu estudares mais, passas no exame.
If you study more, you'll pass the exam.
Se + indicative is grammatical Portuguese but encodes habitual meaning (every time you study). For a realistic future condition, use the future subjunctive.
❌ Sempre que vieres, estou cá. (acceptable but note register)
Correct as open future. Only flag this if your target meaning is habitual (each time now and in future), in which case use present indicative: *Sempre que vens, estou cá.*
✅ Sempre que vieres, estou cá.
Whenever you come, I'll be here. (open future) — vs. *sempre que vens*, *every time you come*, habitual.
This is not a mistake, just a reminder that sempre que genuinely accepts both moods, and they mean different things. Match the mood to your intended meaning.
Key takeaways
- Formation rule: take the 3pl preterite, drop -am, add (-), -es, (-), -mos, -em. Works for every regular verb.
- All three verb classes (-ar, -er, -ir) follow the identical pattern — the class-characteristic vowel stays in the stem.
- Regular future subjunctive singular forms coincide with the infinitive. This is a historical feature, not a source of ambiguity: the conjunction or preposition tells you which tense is in play.
- The full paradigm of the future subjunctive coincides with the personal infinitive for regular verbs. You are learning both at once.
- Spelling patterns like -car, -gar, -çar cause no complications because the ending always starts with -r.
- After quando, se, assim que, logo que, enquanto, sempre que, depois que, mal, como, conforme, and after indefinite quem / o que / onde, this tense is obligatory in European Portuguese.
Next, tackle the irregular forms — ser, ir, ter, estar, vir, ver, saber, poder, querer, fazer, dizer, trazer, pôr — which build on irregular preterite stems and must be learned individually.
Related Topics
- Future Subjunctive OverviewB1 — The futuro do conjuntivo — a living, everyday tense in European Portuguese that marks uncertain future events after temporal, conditional, and relative triggers. Almost extinct in Spanish; thriving in Portuguese.
- Irregular Future Subjunctive FormsB1 — The handful of Portuguese verbs whose future subjunctive is built from an irregular preterite stem — ser/ir, ter, estar, poder, querer, saber, fazer, dizer, trazer, vir, ver, pôr, dar, haver — with full paradigms and use in everyday sentences.
- Preterite: Regular -ar VerbsA2 — Conjugating regular -ar verbs in the preterite
- Preterite: Regular -er and -ir VerbsA2 — Conjugating regular -er and -ir verbs in the preterite
- Personal Infinitive: OverviewB1 — The infinitivo pessoal — an infinitive that conjugates for person and number — is Portuguese's signature grammatical feature, and one of the things that makes the language feel unlike the rest of Romance.
- Subjunctive Mood OverviewB1 — What the conjuntivo is in European Portuguese, why it exists, and when the language requires it — a tour of irrealis across the present, imperfect, and future subjunctive