An adverbial clause (oração subordinada adverbial) is a subordinate clause that modifies the main-clause verb, the main-clause predicate, or the main clause as a whole. It does the work an adverb would do: telling us when something happens, why, how, under what condition, in spite of what, for what purpose, with what result, in comparison to what. Where a complement clause is the clausal analogue of a noun and a relative clause is the clausal analogue of an adjective, the adverbial clause is the clausal analogue of an adverb — a frame around the main event.
Adverbial clauses are where Portuguese subordination gets genuinely rich. Each semantic type has its own list of subordinators, its own mood preferences, and its own interaction with the non-finite forms (infinitive, personal infinitive, gerund). This page walks through the eight main families — temporal, causal, final, conditional, concessive, consecutive, comparative, and modal — and gives you the working decision tree for the two decisions you make on every adverbial clause you produce: which subordinator and which mood.
The canonical reference for this territory is Mateus et al. (2003), Gramática da Língua Portuguesa, chapters 17–19, and Raposo et al. (2013), Gramática do Português, vol. II. We follow their taxonomy here.
The taxonomy in one table
| Type | Asks | Typical subordinators | Mood |
|---|---|---|---|
| Temporal | when? | quando, enquanto, logo que, assim que, sempre que, antes que, depois que, até que, desde que, cada vez que | indicative, future subjunctive, or subjunctive (see below) |
| Causal | why? | porque, já que, visto que, uma vez que, dado que, pois, como | indicative |
| Final / purpose | what for? | para que, a fim de que; para + inf | subjunctive (finite) / infinitive |
| Conditional | if what? | se, caso, desde que, a não ser que, a menos que | indicative / future subjunctive / imperfect subjunctive (by pattern) |
| Concessive | despite what? | embora, ainda que, mesmo que, se bem que, por mais que, apesar de que | subjunctive |
| Consecutive / result | with what result? | tão... que, tanto... que, de modo que, de tal maneira que | indicative (or subjunctive for intended result) |
| Comparative | compared to what? | como, conforme, do que, quanto, como se | indicative (como se + imperfect subjunctive) |
| Modal / manner | how? | como, sem que, sem + inf | indicative / subjunctive (with sem que) |
Memorise this table. Every adverbial clause you encounter will fit somewhere in it.
Temporal clauses
Temporal clauses answer when? They are the most subtle of the adverbial types, because mood depends on whether the temporal reference is factual-past, ongoing, or future-hypothetical.
Past or habitual reference: indicative
When the temporal clause refers to something that has happened, is habitually true, or is currently true, the verb is in the indicative.
Quando cheguei a casa, o jantar já estava frio.
When I got home, dinner was already cold. (past — indicative)
Enquanto estudavas para o exame, eu fazia o jantar.
While you were studying for the exam, I was making dinner.
Sempre que vou a Coimbra, passo pela Sé Velha.
Every time I go to Coimbra, I pass by the old cathedral.
Cada vez que ela me liga, tem sempre má notícia.
Every time she calls me, she always has bad news.
Future reference: future subjunctive
This is the trap for English speakers. When the temporal clause refers to a future event (a point in time that has not yet arrived), Portuguese uses the future subjunctive (futuro do conjuntivo), not the present indicative.
Quando chegares a casa, liga-me.
When you get home, call me. (future — future subjunctive)
Enquanto não melhorares, é melhor ficares em casa.
As long as you don't get better, you'd better stay home.
Logo que souberes o resultado, diz-me.
As soon as you find out the result, tell me.
Assim que puder, vou ter contigo.
As soon as I can, I'll come and meet you.
Sempre que precisares de alguma coisa, pede.
Whenever you need anything, ask.
English makes do with the present ("when you arrive") or an unmarked form, but Portuguese has the morphologically distinct future subjunctive specifically for this environment. The rule is mechanical: if the when-clause points to a future event, the future subjunctive is obligatory.
Antes que and antes de: inherently future-oriented
Antes que ("before") always describes an event that has not happened (from the perspective of the main clause), so it takes the subjunctive unconditionally — present or imperfect, not future.
Termina o trabalho antes que o chefe chegue.
Finish the work before the boss arrives.
Saí antes que ele me visse.
I left before he saw me.
The non-finite counterpart antes de + infinitive is extremely common when the subjects match or can be encoded with the personal infinitive.
Antes de sair, fecha as janelas.
Before leaving, close the windows. (same subject — plain infinitive)
Antes de chegarmos ao aeroporto, lembra-te de desligar o gás.
Before we get to the airport, remember to turn off the gas. (different subject — personal infinitive)
Depois que / depois de: the mirror image
Depois que describes a completed event, so it takes the indicative.
Depois que o filme acabou, fomos jantar.
After the film ended, we went to dinner.
The non-finite depois de + infinitive is again the natural spoken choice.
Depois de saírem, apaguem as luzes.
After you leave, turn off the lights. (personal infinitive)
Depois de acabar o trabalho, vou descansar.
After I finish work, I'm going to rest. (same subject — plain infinitive)
Até que / desde que (temporal)
Até que ("until") takes the subjunctive when the end point lies in the future; it can take the indicative when describing a past completed event.
Esperei até que ele chegasse.
I waited until he arrived. (past, subordinate subjunctive)
Fica aqui até que eu volte.
Stay here until I come back. (future, subjunctive)
Insistiu até que lhe deram razão.
He insisted until they admitted he was right. (past indicative possible in colloquial usage)
Desde que in its temporal meaning ("since," marking a starting point) takes the indicative:
Desde que ele se mudou para Lisboa, quase não nos vemos.
Since he moved to Lisbon, we hardly see each other.
Do not confuse this temporal desde que with its conditional reading ("provided that"), which takes the subjunctive. The two are discussed in the conditional section.
Causal clauses
Causal clauses answer why? They take the indicative, because they assert the cause as a fact.
Não fui à festa porque estava cansadíssimo.
I didn't go to the party because I was exhausted.
Já que estás aqui, ajuda-me a pôr a mesa.
Since you're here, help me set the table.
Visto que o comboio está atrasado, vamos tomar um café.
Since the train is delayed, let's have a coffee.
Uma vez que todos concordam, podemos avançar.
Given that everyone agrees, we can move forward.
Dado que a situação é grave, tomámos medidas imediatas.
Given that the situation is serious, we took immediate measures.
There are register differences among these subordinators. Porque is neutral. Já que, visto que, uma vez que, dado que are more formal, typical of written registers and public speaking. Pois as a causal ("for, because") is literary.
Não insistas, pois ele já tomou a decisão.
Don't insist, for he's already made up his mind. (literary)
Como causal (in initial position)
Como can introduce a causal clause, but only when the clause is fronted:
Como estava a chover, ficámos em casa.
Since it was raining, we stayed home. (fronted como-clause)
❌ Ficámos em casa como estava a chover.
Incorrect — causal como must be fronted.
A trailing como is either manner or comparative, not causal.
Por + infinitive: compact causal
A very common compact causal construction uses por with the infinitive:
Foi castigado por ter mentido.
He was punished for having lied.
Por serem simpáticos, foram convidados para o jantar.
Because they were friendly, they were invited to dinner. (personal infinitive)
This is the causal counterpart of para + infinitive (purpose). Portuguese uses this kind of non-finite adverbial construction constantly, and it is worth building intuition for.
Final (purpose) clauses
Final clauses answer what for? — they express the goal of the main-clause action. They always take the subjunctive when finite, because the purpose is not an asserted fact but a desired outcome.
Estudo muito para que os meus pais fiquem orgulhosos.
I study a lot so my parents will be proud.
Falei mais devagar a fim de que ele me percebesse.
I spoke more slowly so that he would understand me.
When the subjects of the two clauses match, Portuguese strongly prefers the non-finite construction with para + infinitive.
Estudo muito para ter boas notas.
I study a lot to get good grades. (same subject — plain infinitive)
Falei mais devagar para ele perceber.
I spoke more slowly so he would understand. (different subject, personal infinitive implied — 'ele perceber')
Telefonei-te para saberes a novidade.
I called you so you would know the news. (personal infinitive)
In modern European Portuguese, para + personal infinitive has largely replaced para que + subjunctive in spoken use. Para que persists in formal writing and in sentences where the personal infinitive would be clumsy.
Conditional clauses
Conditional clauses answer if what? — they specify the condition under which the main-clause event applies. Mood depends on the type of condition.
Real future conditions: se + future subjunctive
When the condition is a real (open) future possibility, Portuguese uses se + future subjunctive. The main clause is in the future indicative or present.
Se fizer bom tempo amanhã, vamos à praia.
If the weather is nice tomorrow, we'll go to the beach.
Se vires a Ana, diz-lhe que lhe telefonei.
If you see Ana, tell her I called her.
Se puderes, traz pão quando vieres.
If you can, bring some bread when you come.
Once again, the future subjunctive is obligatory — this is not the place for the present indicative. (English's "if you see Ana" maps to se vires a Ana, not *se vês a Ana.)
Real present/general conditions: se + present indicative
When se describes a general fact or a present-time condition with no specifically future reference, the present indicative is used.
Se trabalhas muito, cansas-te.
If you work a lot, you get tired. (general truth — indicative)
Se chove, não vou correr.
If it rains, I don't go running. (habitual — indicative)
Counterfactual / unreal conditions: se + imperfect subjunctive
When the condition is contrary-to-fact or imagined, Portuguese uses se + imperfect subjunctive, with the main clause in the conditional (or imperfect indicative in spoken register).
Se eu fosse rico, comprava uma casa em Sintra.
If I were rich, I would buy a house in Sintra.
Se tivesses chegado mais cedo, tínhamos apanhado o filme.
If you had arrived earlier, we would have caught the film.
Se pudesse voltar atrás, escolhia outro curso.
If I could go back, I would choose a different degree course.
Caso + present subjunctive
Caso is a more formal alternative to se for open future conditions. It takes the present subjunctive, not the future subjunctive.
Caso precises de ajuda, liga-me.
Should you need help, call me. (formal alternative to 'se precisares')
Caso haja alteração de planos, avisamos com antecedência.
In case there's a change of plans, we'll let you know in advance.
Desde que / contanto que (conditional): "provided that"
When desde que has a conditional reading ("provided that"), it takes the subjunctive.
Podes sair desde que voltes cedo.
You can go out provided that you come back early.
Empresto-te o carro desde que o devolvas no sábado.
I'll lend you the car, provided you give it back on Saturday.
Compare the temporal reading of desde que, which means "since [a point in time]" and takes the indicative: Desde que ele se mudou, não nos vemos. Context disambiguates.
A não ser que / a menos que: "unless"
Both take the subjunctive — they express a negative conditional, essentially "if not X."
Vou à festa, a não ser que chova.
I'll go to the party unless it rains.
Não te posso ajudar a menos que me expliques o problema.
I can't help you unless you explain the problem to me.
Concessive clauses
Concessive clauses answer despite what? — they describe a circumstance that would ordinarily block the main-clause event but does not. Nearly all concessive subordinators in Portuguese take the subjunctive, because the concession is presented as not quite asserted — it acknowledges the situation without fully endorsing it as a relevant fact.
Embora esteja a chover, vou sair.
Although it's raining, I'm going out.
Ainda que me peças, não volto lá.
Even if you ask me, I won't go back there.
Mesmo que custe caro, quero comprar esse livro.
Even if it costs a lot, I want to buy that book.
Se bem que ele tenha razão, não gosto da maneira como o disse.
Although he's right, I don't like the way he said it.
Por mais que eu tente, não consigo convencê-lo.
However much I try, I can't convince him.
The non-finite counterpart uses apesar de + infinitive (or personal infinitive):
Apesar de estar cansado, fui ao ginásio.
Despite being tired, I went to the gym.
Apesar de eles terem estudado, o exame correu mal.
Despite their having studied, the exam went badly. (personal infinitive)
Apesar de que + finite clause exists but is less natural than the non-finite version, and many native speakers consider it a calque from Spanish.
Consecutive (result) clauses
Consecutive clauses answer with what result? They take the indicative when describing an actual result, and the subjunctive when describing an intended or hypothetical one.
Falou tão depressa que ninguém percebeu nada.
He spoke so fast that no one understood anything. (actual result — indicative)
O café estava tão forte que tive de o deitar fora.
The coffee was so strong that I had to throw it away.
Estava tanta gente que não cabia ninguém mais.
There were so many people that no one else could fit.
De modo que and de maneira que show a subtle indicative/subjunctive split depending on reading: result (indicative) vs purpose (subjunctive).
Falei devagar, de modo que ele percebeu tudo.
I spoke slowly, so that he understood everything. (result — indicative)
Fala devagar, de modo que ele perceba tudo.
Speak slowly, so that he understands everything. (purpose — subjunctive)
The same subordinator can head either type of clause; the mood disambiguates.
Comparative clauses
Comparative clauses answer compared to what? and take the indicative — they assert a comparison as factual.
Ele fala português como se tivesse nascido cá.
He speaks Portuguese as if he'd been born here. (como se + imperfect subjunctive)
Faz conforme te ensinaram.
Do as they taught you.
Quanto mais estudas, mais aprendes.
The more you study, the more you learn.
É mais difícil do que eu pensava.
It's harder than I thought.
The important special case is como se ("as if"), which describes a counterfactual comparison and always takes the imperfect subjunctive — never the indicative.
Olhou para mim como se não me conhecesse.
He looked at me as if he didn't know me.
Falas como se soubesses tudo.
You talk as if you knew everything.
Modal / manner clauses
Modal clauses answer how? They take the indicative with como (manner) and the subjunctive with sem que (without X-ing, when subjects differ).
Fez o trabalho como lhe pediram.
He did the work as they asked him to.
Saiu sem que ninguém o notasse.
He left without anyone noticing.
Saiu sem dizer nada.
He left without saying anything. (same subject — plain infinitive)
Trabalhámos dois dias sem eles dormirem.
We worked for two days without them sleeping. (different subject — personal infinitive)
The decision tree
Here is the decision procedure every advanced learner should internalise for adverbial clauses:
- Identify the semantic type — temporal, causal, final, conditional, concessive, consecutive, comparative, modal.
- Identify the subordinator — this often settles the mood directly (embora, antes que, sem que, para que → subjunctive; porque, já que → indicative).
- If the subordinator is temporal or conditional, check the time reference:
- past/habitual/present-general → indicative;
- future → future subjunctive (for se, quando, enquanto, sempre que, logo que, assim que);
- future non-real (counterfactual) → imperfect subjunctive.
- If the subjects of the two clauses match, consider whether a non-finite construction (plain infinitive) is more natural. Often it is.
- If the subjects differ but a preposition takes an infinitive (antes de, depois de, para, por, sem, apesar de, até), use the personal infinitive.
Common Mistakes
❌ Quando chegas amanhã, liga-me.
Incorrect — 'quando' with a future event requires the future subjunctive.
✅ Quando chegares amanhã, liga-me.
When you arrive tomorrow, call me.
English uses the present for future in when-clauses; Portuguese does not. This is one of the highest-frequency errors.
❌ Se vejo a Ana, digo-lhe.
Incorrect — open future condition requires future subjunctive.
✅ Se vir a Ana, digo-lhe.
If I see Ana, I'll tell her.
❌ Embora está a chover, saímos.
Incorrect — 'embora' requires the subjunctive. Full stop.
✅ Embora esteja a chover, saímos.
Although it's raining, we're going out.
❌ Para que eu percebo, fala devagar.
Incorrect — 'para que' takes the subjunctive.
✅ Para que eu perceba, fala devagar.
So I can understand, speak slowly.
❌ Antes de eles chegar, preparei tudo.
Incorrect — different subject requires personal infinitive.
✅ Antes de eles chegarem, preparei tudo.
Before they arrived, I had everything ready.
❌ Ele olha para mim como se não me conhece.
Incorrect — 'como se' always takes imperfect subjunctive.
✅ Ele olha para mim como se não me conhecesse.
He looks at me as if he didn't know me.
❌ Porque estava a chover, ficámos em casa.
Marked and often judged as a Spanish/English-style anglicism. Fronted causal should use 'como'.
✅ Como estava a chover, ficámos em casa.
Since it was raining, we stayed home.
This one is a genuine stylistic point. Porque at the head of a sentence is increasingly heard in colloquial PT-PT under the influence of English and Spanish, but traditional prescriptive grammar reserves initial porque for embedded questions (Perguntei porque chegou tarde) and uses como for fronted causals. In careful writing, follow como.
❌ Desde que ele mude, vou gostar mais dele.
Ambiguous. With the conditional reading ('provided that'), the subjunctive is fine, but without context this sentence is unclear.
✅ Desde que ele mude a atitude, vou gostar mais dele.
Provided he changes his attitude, I'll like him more. (conditional)
✅ Desde que ele se mudou, quase não o vejo.
Since he moved away, I hardly see him. (temporal)
Key Takeaways
- Adverbial clauses modify the main verb or the whole main clause. Eight main types: temporal, causal, final, conditional, concessive, consecutive, comparative, modal.
- Temporal clauses take the future subjunctive for future reference (quando chegares), indicative for past/habitual, and subjunctive after antes que.
- Causal clauses take the indicative (porque, já que, visto que). Fronted causal is como, not porque.
- Final clauses take the subjunctive with para que. Same-subject: use para
- infinitive. Different-subject: often para
- personal infinitive.
- infinitive. Different-subject: often para
- Conditional se-clauses: future subjunctive for open future, imperfect subjunctive for counterfactual, present indicative for general conditions.
- Concessive clauses take the subjunctive unconditionally (embora, ainda que, mesmo que, se bem que, por mais que). Non-finite counterpart: apesar de
- inf.
- Consecutive clauses take the indicative for actual result, subjunctive for intended/hypothetical (de modo que, disambiguated by mood).
- Comparative como se always takes the imperfect subjunctive.
- The personal infinitive is the compact different-subject form Portuguese prefers after antes de, depois de, para, por, sem, apesar de, até — more natural than a finite que-clause.
- When a subordinator triggers the subjunctive inherently (embora, para que, antes que, sem que, caso, a não ser que), no amount of contextual reasoning overrides it. Memorise the closed list.
Related Topics
- Subordination OverviewB1 — The main types of subordinate clauses in European Portuguese — substantive, adjective, and adverbial — with finite and non-finite variants and the logic of mood selection.
- Complement ClausesB1 — Clauses that function as subject or object of a verb — finite que-clauses with indicative or subjunctive, non-finite infinitival complements, embedded questions, and subject-raising.
- Portuguese Syntax OverviewA1 — The rules governing word order and sentence structure in European Portuguese — a high-level tour of how sentences are built.
- Concessive Clauses (Embora, Apesar De, Mesmo Que)B1 — Saying although/even though/despite in Portuguese — the family of conjunctions that pair with the subjunctive, the infinitive, or (rarely) the indicative.
- 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.