The infinitive is the dictionary form of a Spanish verb — hablar (to speak), comer (to eat), vivir (to live). But it is also far more than that. The infinitive is the workhorse non-finite verb form: it serves as a noun, sits after prepositions, completes modal verbs, gives impersonal commands, and appears in dozens of fixed constructions. Learning where the infinitive belongs — and where it does not — is one of the highest-yield investments a Spanish learner can make, because the alternative an English speaker reaches for (the -ing form) is almost always wrong.
The three endings
Every Spanish infinitive ends in -r, preceded by -a, -e or -i. These three endings define the three conjugation classes that the rest of Spanish grammar leans on.
| Ending | Class | Examples |
|---|---|---|
| -ar | First conjugation (largest) | hablar, comprar, trabajar, llegar, mirar |
| -er | Second conjugation | comer, beber, leer, vender, aprender |
| -ir | Third conjugation | vivir, escribir, abrir, subir, recibir |
About 80% of Spanish verbs are -ar; the rest split roughly evenly between -er and -ir. New verbs entering the language — coined from English, technology, slang — are almost always -ar: tuitear, guglear, flipar, postear.
The three forms of the infinitive
A single Spanish verb actually has three infinitives, each with a different job.
1. Simple infinitive: hablar
The basic dictionary form. Refers to an action without tense or person.
Quiero hablar contigo un momento.
I want to speak with you for a moment.
2. Compound infinitive: haber hablado
Formed with the infinitive of haber plus the past participle. Refers to an action prior to another action — the "to have done" form.
Me arrepiento de haber hablado tan rápido.
I regret having spoken so quickly.
The compound infinitive lets Spanish make a sequence of events explicit without needing a finite verb. In English we sometimes do the same with "having + past participle", but Spanish reaches for this much more often, especially after por, de, después de and similar prepositions.
3. Reflexive infinitive: levantarse
When the verb is reflexive, the pronoun attaches to the end of the infinitive as a single word: levantarse (to get up), acostarse (to go to bed), irse (to leave), quedarse (to stay).
No quiero levantarme tan temprano mañana.
I don't want to get up so early tomorrow.
The clitic agrees with the subject of the main clause: quiero levantarme, quieres levantarte, quiere levantarse, queremos levantarnos, queréis levantaros, quieren levantarse. The infinitive itself never inflects — only the attached pronoun changes.
What the infinitive does — the full menu
The infinitive plays at least six distinct roles in Spanish grammar. Each role has its own dedicated page; this section is the map.
1. As a verbal noun (subject or object)
The infinitive can function as a noun, taking the place a noun would otherwise occupy: as the subject, as the direct object, after a verb like gustar or encantar. This is where English uses an -ing form, but Spanish uses the infinitive.
Nadar es divertido.
Swimming is fun.
Me encanta cocinar los domingos.
I love cooking on Sundays.
Ver la tele todo el día no es saludable.
Watching TV all day isn't healthy.
This is the single most important fact about the Spanish infinitive for English speakers: swimming is fun is nadar es divertido, not nadando es divertido. The gerund nadando cannot be a subject in Spanish — it has no nominal function.
2. After prepositions
After any preposition, Spanish uses the infinitive — never the gerund. Antes de comer (before eating), después de llegar (after arriving), sin pensar (without thinking), para estudiar (in order to study), al salir (upon leaving).
Cierra la puerta al salir, por favor.
Close the door on your way out, please.
No puedo dormir sin tomar un vaso de agua antes.
I can't sleep without drinking a glass of water first.
This is non-negotiable: there is no preposition + gerund construction in standard Spanish. The English ear wants después de comiendo; the Spanish ear hears that as broken grammar. See the dedicated page on this rule.
3. After modal verbs (no preposition)
A small set of verbs takes a bare infinitive with no connecting preposition: poder, querer, deber, saber, soler, preferir, necesitar, intentar. These are the modal verbs — they modify the meaning of the infinitive that follows.
Puedo ayudarte mañana si quieres.
I can help you tomorrow if you want.
Sé nadar pero no muy bien.
I know how to swim, but not very well.
Sueles llegar tarde a las reuniones.
You usually arrive late to meetings.
Note that querer takes a bare infinitive only when the subject is the same as the modal: quiero ir (I want to go). When the subjects differ, you switch to querer que + subjunctive: quiero que vayas (I want you to go). This shift from infinitive to que + subjunctive is the central pivot point of intermediate Spanish.
4. After other verbs with a preposition
Many verbs take the infinitive but require a specific preposition between them: empezar a + inf (empezar a llover), acabar de + inf (acabar de comer), aprender a + inf, tratar de + inf, insistir en + inf, soñar con + inf. The preposition is part of the verb and must be memorised.
Estoy aprendiendo a tocar la guitarra.
I'm learning to play the guitar.
Acabo de hablar con tu hermana.
I just spoke with your sister.
5. As an impersonal command (signs, recipes)
Infinitives appear on signs, in manuals and in cookbook instructions as impersonal commands. No fumar (no smoking), empujar (push), agitar bien antes de usar (shake well before use), pelar las patatas (peel the potatoes).
No pisar el césped.
Keep off the grass.
This is the natural register for an impersonal written instruction. Using tú or usted imperative on a sign would sound either too intimate or too formal, depending on the choice — the infinitive sidesteps the question by addressing nobody specifically.
6. After verbs of perception
After ver, oír, escuchar, sentir and similar verbs of perception, Spanish uses a bare infinitive (or a gerund — both are possible, with a slight aspectual difference).
Te vi llegar esta mañana desde la ventana.
I saw you arrive this morning from the window.
Oí a los niños gritar en el patio.
I heard the children shout in the courtyard.
The infinitive emphasises the completed event (you arrived); the gerund (te vi llegando) emphasises the ongoing action (you were in the middle of arriving). Both are valid; native speakers pick depending on which aspect they want to foreground.
The infinitive vs the gerund — the cardinal contrast
English-speaking learners' single biggest infinitive-related error is assuming Spanish uses the gerund (-ando / -iendo) the same way English uses the -ing form. It doesn't. Spanish reserves the gerund for two narrow roles: forming progressive tenses with estar (está hablando), and acting as an adverb describing how an action is done (entró corriendo = he came in running). Everywhere else where English would use -ing, Spanish uses the infinitive.
| English | Spanish | Why |
|---|---|---|
| Swimming is fun. | Nadar es divertido. | Subject = infinitive, not gerund |
| I like reading. | Me gusta leer. | Object of gustar = infinitive |
| Before eating, wash your hands. | Antes de comer, lávate las manos. | After preposition = infinitive |
| I can swim. | Sé nadar. | After modal = infinitive |
| She is swimming. | Está nadando. | Progressive = gerund (one of the two real gerund uses) |
| He came in running. | Entró corriendo. | Adverbial manner = gerund (the other real use) |
If you can keep the bottom two rows separate from the top four, you will get this right ninety-nine times out of a hundred.
A note on peninsular vosotros with the infinitive
In Spain, the vosotros form is the default plural-familiar, and it interacts with the infinitive just like any other person. There is no special infinitive form for vosotros — the construction is always [vosotros conjugated verb] + infinitive.
Podéis venir cuando queráis, no hay prisa.
You guys can come whenever you want, there's no rush.
Vosotros tenéis que aprender a escuchar antes de hablar.
You guys have to learn to listen before speaking.
Common Mistakes
❌ Nadando es divertido.
Incorrect — gerund cannot be a subject in Spanish.
✅ Nadar es divertido.
Swimming is fun.
❌ Antes de comiendo, lávate las manos.
Incorrect — preposition always takes infinitive, never gerund.
✅ Antes de comer, lávate las manos.
Before eating, wash your hands.
❌ Quiero que ir contigo.
Incorrect — same subject takes bare infinitive, no que.
✅ Quiero ir contigo.
I want to go with you.
❌ Me gusta leyendo libros.
Incorrect — object of gustar is infinitive, not gerund.
✅ Me gusta leer libros.
I like reading books.
❌ No quiero me levantar temprano.
Wrong clitic placement — attach to the infinitive itself.
✅ No quiero levantarme temprano. (or: No me quiero levantar temprano.)
I don't want to get up early.
Key takeaways
- The infinitive ends in -ar, -er or -ir. There are three of them per verb: simple (hablar), compound (haber hablado) and reflexive (levantarse, irse, acostarse — only for verbs that are inherently reflexive).
- It functions as a noun, follows prepositions, completes modals, gives impersonal commands and appears after verbs of perception.
- Wherever English uses an -ing form as a noun, Spanish uses the infinitive — never the gerund.
- The Spanish gerund (-ando / -iendo) is for progressive tenses and adverbial manner only. Keep the two forms in completely separate mental folders.
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Start learning Spanish→Related Topics
- El infinitivo como sustantivoB1 — How Spanish turns a verb into a noun — fumar es malo, me gusta cocinar, el comer demasiado engorda — and why the gerund cannot do this job.
- Infinitivo después de preposiciónA2 — The iron rule of Spanish syntax: any preposition is followed by the infinitive, never the gerund — antes de comer, sin pensar, para estudiar, después de llegar.
- Infinitivo después de verbos conjugadosA2 — When two verbs share a subject, the second one stays in the infinitive — quiero ir, puedo venir, suelo madrugar — never que, never a conjugated form.
- Al + infinitivo: 'upon doing'B1 — The al + infinitivo construction marks the moment one action triggers another — al llegar a casa, me di cuenta — covering English 'upon', 'when' and 'as soon as' in one compact form.
- Alternativas al imperativo: infinitivo, presente, hay queB1 — How Spanish gives commands without the imperative — bare infinitives on signs, present-indicative recipe instructions, hay que for general advice, and the colloquial peninsular 'callar/sentaros'.
- Errores: traducciones literalesB1 — The constituent words map but the construction doesn't. 'I'm good' (no, thanks) is NOT 'estoy bueno'. 'My name is Juan' is more naturally 'me llamo Juan'. The high-frequency calque traps for English speakers in everyday peninsular Spanish.