Kilo Lingo
Spanish grammar Part of Chapter 7

CEFR A1-B1

5 min read

Test yourself (28 questions)

Spanish Obligation: tener que, hay que, deber and necesitar

By Michael McGettrick and Sergio Linares-HernandesUpdated 12 October 2026

Spanish says "must", "have to" and "should" with four structures, each followed by an infinitive. Pick by two questions: is a person named, and is it circumstance, duty or need?

Quick check

Three quick questions on what you have just read. The full practice is further down.

Pick the right one

0/3

Choose the form that matches the meaning in brackets.

  1. Mañana madrugar: mi vuelo sale a las seis. (I have to)

  2. Para entrar en el museo comprar una entrada. (a general rule, no named person)

  3. No fumar aquí: está prohibido. (you mustn't)

tener quehay quedeberthe part that changesWhat do the colours mean?
  • . - I have to work.
  • . - You have to book.

Which one do I use? The decision chart

You meanUseExample
I have to (a plan) . I have to go out.
Anyone has to . You have to wait.
Must (duty, a rule) . You must tell the truth.
Should (advice) . You should sleep more.
Need to . I need to rest.
Don't have tono . You don't have to come.
Mustn'tno . You mustn't touch that.
Must be (a guess) . He must be at home.

All of them are verbal periphrases: the first verb is conjugated, the second stays an infinitive.

tener que + infinitive: personal obligation

tener quehay quethe part that changesWhat do the colours mean?

The workhorse, and the one to reach for first. Only changes for the person; and the infinitive never move:

tener (changes)
que
Infinitive
.
.
.
.
Persontener que
yo
, ,
,
  • . - I have to work on Saturday.
  • ¿ ? - Do you have to go already?

The obligation usually comes from outside: a job, a timetable, a situation. It is in tone, and the commonest of the four in conversation.

hay que + infinitive: the impersonal one

says something is necessary without saying who has to do it. English says "you", "one" or uses a passive:

  • . - You have to book a table.
  • . - One has to be patient.

is the impersonal form of haber, so it never changes for person or number. It changes only for tense, and stays singular:

TenseFormEnglish
present you have to
imperfect you had to (back then)
preterite you had to (and did)
future you will have to
conditional we ought to, one should
  • . - We'll have to see.

deber + infinitive: duty and advice

Deber carries the weight of a rule or a moral judgement:

  • . - You must tell the truth.
  • . - Pupils must respect the rules.

In the present it can sound stern. For advice, use the conditional , the natural "should":

MeaningSpanishEnglish
should .You should sleep more.
shouldn't .We shouldn't be late.
should have .I should have called you.
should have .I should have called you.

With a noun instead of an infinitive, means "to owe": . - I owe you ten euros.

necesitar: plain need

Necesitar is need rather than obligation, exactly like English "need":

PatternSpanishEnglish
+ infinitive .I need to sleep.
+ noun¿ ?Do you need help?
+ subjunctive .I need you to help me.
.You need a passport.

When someone else does it, the verb after goes into the present subjunctive, because the two verbs now have different subjects. is the impersonal cousin, like .

The negative trap: don't have to vs mustn't

English has the same split, but learners treat and as twins and negate the wrong one:

OptionalForbidden
  1. no tienes que
  2. no deberías
  3. no debes
  • . - You don't have to come. (it's up to you)
  • . - You shouldn't come. (better not)
  • . - You mustn't come. (it's forbidden, or wrong)

Say to a guest and you have told them paying is wrong, not that it is on the house. sits in between: there's no need to exaggerate, or one shouldn't.

In the past: tuve que vs tenía que

The obligation verbs follow the usual preterite vs imperfect split:

TenseSpanishEnglish
preterite .I had to go to the doctor (and went).
imperfect , .I was supposed to go, but didn't.
imperfect .I had to work on Saturdays (a habit).
preterite .A doctor had to be called.
imperfect .You had to queue (that was how it was).

Must as a guess: deber de

+ infinitive is not a duty but a supposition, like English "he must be at home":

  • . - He must be at home. (I suppose)
  • . - It must be about five.

The RAE's Diccionario panhispánico advises against for obligation but accepts plain for a guess, and speakers blur the two. So the rule runs one way: never add when you mean duty. Guessing has its own page, the future and conditional of probability.

In formal or written Spanish you will also meet for obligation: . - I must admit you were right. Recognise it; you do not need it.

Mistakes English speakers make

WrongRightWhy
. . needs
. . takes no
. . never goes plural
Yo . . names no one
No . .no means mustn't
. . makes it a guess
. .another subject: + subj.

What to do next

  1. Default to ; use when nobody in particular is meant.
  2. In the negative, check: optional ( ) or forbidden ( )?
  3. Do the story and spot-the-mistake drills below.

Practise: test yourself

Pick the right one

0/8

Choose the form that matches the meaning in brackets.

  1. Mañana madrugar: mi vuelo sale a las seis. (I have to)

  2. Para entrar en el museo comprar una entrada. (a general rule, no named person)

  3. No fumar aquí: está prohibido. (you mustn't)

  4. No venir si estás cansado. (you don't have to)

  5. Tu hermano no contesta; estar dormido. (he must be, a guess)

  6. Ayer ir al médico, así que no fui a clase. (I had to, and did)

  7. llamarla, pero se me olvidó. (I was supposed to)

  8. En aquella época trabajar los sábados. (one had to)

Spot the mistake

0/5

Tap the mistake.

Complete the story

0/4

Choose the form that fits each gap.

Moving day

Mañana yo salir temprano, porque el camión llega a las siete. Para entrar en el edificio pedir permiso. Tú no venir si no quieres, pero llamar a tu madre: está sola.

Gap 1 of 4

Fill in the blank

0/6

Put the verb in brackets into the right form.

  1. Tú que estudiar más. (tener) (tener que, tú form)

  2. Nosotros que irnos ya. (tener) (tener que, nosotros form)

  3. Mañana que madrugar. (haber, future) (impersonal, so third person singular)

  4. Los alumnos respetar las normas. (deber, present) (deber + infinitive, a duty)

  5. descansar más, estás agotado. (deber, conditional, tú) (the soft should)

  6. Mi padre que trabajar todo el fin de semana pasado. (tener, preterite) (a completed obligation)

Translation drill

0/5

Translate into Spanish.

  1. I have to work tomorrow.

  2. One has to be patient.

  3. You (tú) should rest.

  4. You (tú) don't have to pay.

  5. We need to talk.

Chapters 1 and 2 free

This article is one lesson in a whole course

Every grammar point has its own article and drill, and the course wraps them in graded stories, games and printable worksheets, in the order you need them.

Chapters 1 and 2 free, forever. Plus: 7 days free, then $5 a month for all eleven languages.

Start learning free

Spanish · Free printables

Practice worksheets and infographics

Practice worksheets with answer keys built in, plus infographic and listicle formats. Open any one to view, print or save.

Free for members

The printable worksheets, infographics and PDFs are free with an account. Start a free week and download as many as you like.

Start your free week

More grammar on this course

Frequently asked questions

What is the difference between and in Spanish?
+ infinitive is 'have to': an obligation that comes from circumstances, a timetable or someone else ( , I have to work on Saturday). + infinitive is 'must' or 'ought to': a duty, a rule or a moral judgement ( , you must tell the truth). In the affirmative they often overlap, and is the more common in speech. In the negative they split: is 'you don't have to go', is 'you mustn't go'.
How do you use in Spanish?
+ infinitive states a general necessity without saying who has to do it: (you have to book a table). is the impersonal form of , so it never changes for person or number: there is no 'hayn ' and no ' '. It does change tense: (you had to), (you will have to), (you would have to). To name the person, use : .
What is the difference between and ?
In careful usage, + infinitive is obligation ( a , he must be home by ten) and + infinitive is a guess ( , he must be at home, I suppose). The RAE's Diccionario panhispánico advises against for obligation but accepts plain for a guess, and speech blurs the two. The safe rule: never add when you mean duty.
How do you say 'you don't have to' in Spanish?
+ infinitive: (you don't have to pay). is just as common: . Do not use , which means 'you mustn't': tells someone that paying is wrong.
Is it or ?
Both are correct and they mean different things. (preterite) is an obligation you carried out: (I had to go to the doctor, and I went). (imperfect) is the obligation as background, often one that did not happen: , (I was supposed to call her, but I forgot).