Ter de / Ter que + Infinitive (Obligation) | Portuguese (Portugal) Grammar

Portuguese has a family of constructions for expressing obligation, necessity, and advice. Of them, ter de + infinitive (and its colloquial twin ter que + infinitive) is the strongest, the most common in speech, and -- thanks to the de vs que choice -- the most debated in prescriptive circles. If English have to has an equivalent in European Portuguese, this is it.

This page walks through both variants, lays out the traditional prescriptive distinction, describes what real speakers actually do, and situates the construction against its neighbors dever ("should," weaker) and precisar de ("need to," more about requirement than duty).

The three pieces

Slot	What fills it	What changes
auxiliary	ter, in some tense	conjugates for person, number, tense
linker	de or que (see below)	does not change form
main verb	bare infinitive	never changes

Whether you pick de or que is a register and tradition question, not a grammatical one. Both are produced by native speakers daily. Both appear in printed newspapers. The choice is discussed below.

Tenho de acabar este relatório até amanhã de manhã.

I have to finish this report by tomorrow morning.

Tens que provar isto, é a melhor sopa que já comi.

You have to try this, it's the best soup I've ever had.

O meu irmão tem de apanhar o comboio das sete.

My brother has to catch the seven o'clock train.

Present paradigm

The present of ter is irregular -- drill it until it is automatic.

Subject	ter (present)	Example with estudar	Meaning
eu	tenho	tenho de / que estudar	I have to study
tu	tens	tens de / que estudar	you have to study
ele / ela / você	tem	tem de / que estudar	he/she/you have to study
nós	temos	temos de / que estudar	we have to study
eles / elas / vocês	têm	têm de / que estudar	they/you have to study

Watch the accents. The third-person plural têm carries a circumflex to mark it as distinct from the singular tem. Without the accent, tem is the form for ele / ela / você; têm is the form for eles / elas / vocês. In speech the two sound identical, but in writing the difference is obligatory.

Eles têm de chegar a horas, senão perdem o voo.

They have to arrive on time, otherwise they'll miss the flight.

Temos de falar com a tua professora sobre as notas.

We have to talk to your teacher about your grades.

The de vs que question

This is the famous distinction, and it deserves direct treatment. Traditional prescriptive grammar (especially in Portugal) distinguishes the two constructions as follows.

Traditional prescriptive rule

Ter de + infinitive -- expresses obligation or necessity. "I have to study" = I am obliged to study. This is the form recommended by strict Portuguese grammarians.
Ter que + infinitive -- originally meant "to have something to V," where que stands for an implicit object: tenho que fazer = "I have things to do." Over time this reading has blurred and the construction has come to overlap fully with ter de.

Under the traditional analysis, tenho de ir ("I must go") and tenho muito que fazer ("I have a lot to do") are distinct constructions. The second contains the relative que, meaning "(things) which"; the first contains the prepositional de, marking pure obligation.

The colloquial reality

In actual spoken and written European Portuguese today, ter de + infinitive and ter que + infinitive are used interchangeably by the vast majority of speakers. The prescriptive distinction has largely collapsed. You will find both variants in newspapers, in novels, on television, and in everyday conversation. A literate Portuguese speaker will recognize both as natural.

That said, there is a real register sliver worth noting:

Ter de + infinitive: slightly more formal, traditional, and preferred in careful writing -- legal texts, formal prose, prescriptive grammar books, official documents.
Ter que + infinitive: slightly more colloquial and conversational. More common in speech. Would not look out of place in a novel or a news article, but a stricter editor might still "correct" it to ter de.

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If you are writing a formal document, a thesis, or a letter to a government office, use ter de. If you are speaking with friends or texting, ter que is perfectly natural. If you are unsure, ter de is never wrong.

What about the "ter que = have something to" reading?

The older construction ter (algo) que + inf survives when there is a clearly relative-clause structure, usually with an explicit noun.

Tenho muito que fazer hoje.

I have a lot (of things) to do today.

Não há nada que discutir.

There is nothing to discuss.

In these cases, que is the relative pronoun and ter que + inf means "to have things to V." This is distinct from the obligation periphrasis and is unambiguous in context.

Paradigms across tenses

The construction is fully productive. Put ter in any tense, and the periphrasis inherits the meaning of that tense.

Imperfect: "had to" (ongoing or habitual past obligation)

Subject	ter (imperfect)	Example
eu	tinha	tinha de / que estudar
tu	tinhas	tinhas de / que estudar
ele / ela / você	tinha	tinha de / que estudar
nós	tínhamos	tínhamos de / que estudar
eles / elas / vocês	tinham	tinham de / que estudar

Quando era criança, tinha de estudar piano três vezes por semana.

When I was a child, I had to practice piano three times a week.

Ela tinha que levantar-se às cinco para apanhar o autocarro.

She had to get up at five to catch the bus.

Preterite: "had to (on a specific occasion)"

Subject	ter (preterite)	Example
eu	tive	tive de / que estudar
tu	tiveste	tiveste de / que estudar
ele / ela / você	teve	teve de / que estudar
nós	tivemos	tivemos de / que estudar
eles / elas / vocês	tiveram	tiveram de / que estudar

Ontem tive de ficar até tarde no escritório.

Yesterday I had to stay late at the office.

Tivemos que cancelar os planos por causa da chuva.

We had to cancel our plans because of the rain.

The distinction between imperfect and preterite here matches the general rule: tinha de describes a recurring or ongoing past obligation; tive de describes a specific past occasion on which obligation arose.

Future: "will have to"

Terás de falar com ele antes do fim do mês.

You'll have to speak to him before the end of the month.

Vamos ter que comprar bilhetes novos.

We'll have to buy new tickets.

Both the synthetic future (terei de) and the analytic ir + inf construction (vou ter de) are possible. In speech, vou ter de / que is more common.

Conditional: "would have to"

Teria de aceitar o emprego, mesmo que não gostasse dele.

I would have to accept the job, even if I didn't like it.

Subjunctive: "that one have to"

Se tivesse de escolher, escolhia o vermelho.

If I had to choose, I'd pick the red one.

Duvido que ele tenha de fazer isso sozinho.

I doubt he'll have to do that alone.

Note: after se expressing a hypothetical, use the imperfect subjunctive (tivesse). After verbs of doubt or emotion, use the present subjunctive (tenha).

Meaning: strong obligation

Ter de + inf (and ter que + inf) expresses a strong obligation -- something the speaker sees as necessary, compulsory, non-negotiable. It is stronger than dever ("should") and sometimes stronger than precisar de ("need to"), depending on context.

Tens de pagar a conta hoje, senão cortam-te a luz.

You have to pay the bill today, otherwise they'll cut your power.

Temos de chegar ao hospital o mais rápido possível.

We have to get to the hospital as fast as possible.

The obligation can come from external circumstances ("the rules require it," "the situation demands it") or from the speaker's own strong judgement ("this absolutely must happen"). It is not typically used for polite suggestions -- for those, dever is the go-to.

Contrast with dever and precisar de

This is where the shades of obligation start to matter.

Construction	Meaning	Strength	Typical use
ter de / que inf	have to, must	strong	External obligation, necessity, non-negotiable
dever inf	should, ought to	weak / advisory	Recommendation, moral suggestion, mild expectation
precisar de inf	need to	moderate	Requirement, practical necessity, want

Compare three variants of the same basic idea:

Tens de estudar mais se queres passar no exame.

You have to study more if you want to pass the exam (strong, no choice).

Deves estudar mais se queres passar no exame.

You should study more if you want to pass the exam (advice).

Precisas de estudar mais se queres passar no exame.

You need to study more if you want to pass the exam (requirement).

All three are grammatical and idiomatic. The speaker's posture shifts: tens de is almost scolding, deves is gentler advice, precisas de is practical observation.

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English have to leans strong; English should leans weak; English need to sits in between. The Portuguese triad maps onto this almost exactly. Don't translate have to as dever -- it downgrades the force by a significant notch.

Negation: "don't have to" vs "must not"

A frequent source of confusion for English speakers: in English, don't have to means "it is not necessary," while must not means "it is forbidden." Portuguese uses different constructions for these two meanings.

Não ter de + inf = "don't have to," "not be obliged to" (lack of obligation).
Não poder + inf = "must not," "can't," "mustn't" (prohibition).

Não tens de vir, se não quiseres.

You don't have to come, if you don't want to.

Não podes sair da sala durante o exame.

You must not leave the room during the exam.

Beware: não deves sair ("you shouldn't leave") softens the prohibition; não podes sair ("you can't leave") enforces it. Pick the verb to match the force.

Object pronouns

With ter de / que + inf, the object pronoun attaches to the infinitive in affirmative sentences with no proclisis trigger.

Tenho de ligar-lhe ainda hoje.

I have to call him today.

Temos que convidá-los para o jantar.

We have to invite them to the dinner.

Note the contraction: convidar + os becomes convidá-los, with -r dropping and the pronoun taking l-.

With a proclisis trigger (não, subordinator, adverb), the pronoun jumps before ter.

Não lhe tenho de dar satisfações.

I don't have to answer to him.

Sei que me tens de dizer a verdade.

I know you have to tell me the truth.

Negation

Não goes before ter, never between ter and the linker.

Não tenho de ir à reunião, não sou obrigada.

I don't have to go to the meeting, I'm not required to.

❌ Tenho não de ir.

Incorrect -- negation must precede ter.

Common mistakes

❌ Tenho que de ir.

Incorrect -- pick one linker, not both.

✅ Tenho de ir. / Tenho que ir.

I have to go.

The linker is either de or que, not both. Choose one and stay with it.

❌ Tens para fazer isto hoje.

Incorrect -- obligation is not expressed with para in this way.

✅ Tens de fazer isto hoje.

You have to do this today.

Spanish uses tener que + inf -- Portuguese matches with ter de or ter que, not with para. Don't let para creep in from other constructions.

❌ Eu devo ir à consulta do médico.

Too weak for a scheduled medical appointment -- dever is advisory.

✅ Eu tenho de ir à consulta do médico.

I have to go to the doctor's appointment.

For a fixed obligation (an appointment, a deadline), ter de is the natural choice. Dever is for advice and mild recommendation.

❌ Eles têm que cancelado os planos.

Incorrect -- the main verb must be in the infinitive, not the participle.

✅ Eles tiveram de cancelar os planos.

They had to cancel the plans.

The main verb in the periphrasis stays in bare infinitive form. To put the whole thing in the past, conjugate ter.

❌ Tem ir.

Incorrect -- the linker de or que is mandatory.

✅ Tem de ir. / Tem que ir.

He/She has to go.

Unlike ir + inf, the ter periphrasis needs a linker. Dropping it is ungrammatical.

Key takeaways

Form: conjugated ter
- de or que
  - bare infinitive. Both linkers are grammatical; both are common.
Present paradigm: tenho / tens / tem / temos / têm de / que + inf. Note the accent on têm.
Register: ter de slightly more formal and traditional; ter que slightly more conversational. Modern EP uses both interchangeably.
Traditional distinction: prescriptively, ter de = obligation, ter que = "have (something) to V." In everyday speech this distinction has blurred, except when que is clearly relative (tenho muito que fazer).
Meaning: strong obligation, necessity, non-negotiable requirement. English have to / must.
Weaker alternatives: dever + inf ("should"), precisar de + inf ("need to").
Negation asymmetry: não ter de + inf = "don't have to" (lack of obligation); não poder + inf = "must not" (prohibition). Don't confuse them.
Pronouns: enclitic on the infinitive by default; proclitic to ter with a trigger.
Across tenses: tinha de / que (had to, imperfect), tive de / que (had to, preterite), terei de / que (will have to), teria de / que (would have to), tivesse de / que (imperfect subjunctive).