What is the preterite of dormir in Spanish?

The preterite of dormir is: dormí, dormiste, durmió, dormimos, dormisteis, durmieron. The third-person forms (durmió, durmieron) shift the stem o to u; all other forms keep the o. The endings are standard -ir preterite endings with regular accents on yo (dormí) and él/ella (durmió).

Why is it durmió instead of dormió?

Dormir belongs to the stem-changing -ir verb family. Verbs with o in the stem shift to u in the third-person preterite forms (durmió, durmieron). This is the same rule that applies to morir (murió, murieron). The other four forms keep the original o.

How is dormir different from dormirse in the preterite?

Dormir means to sleep (the act of sleeping); dormirse means to fall asleep (the moment of transition). Both take identical conjugation, just add the reflexive pronoun: me dormí (I fell asleep) vs. dormí (I slept). The o-to-u stem rule still applies in se durmió, se durmieron.

What other verbs follow the same o-to-u pattern as dormir?

The main verb that shares this exact pattern is morir (to die): morí, moriste, murió, morimos, moristeis, murieron. Both are -ir verbs with o in the stem, and both shift the o to u in third-person preterite forms. Learning dormir gives you morir for free.

How can I learn to use the preterite of dormir naturally?

Dormir appears in any story about sleep, rest, or daily routines, which Parrot's short-form videos surface constantly. Hearing native speakers say dormí, durmió, durmieron in real morning-after conversations locks in the o-to-u shift without explicit drilling. Spaced repetition handles the form recall on the side.

Spanish grammar · Intermediate

Preterite of Dormir: All Forms with Examples

Written by Sofia Ramirez, Lead Spanish Curriculum Editor · Reviewed May 2026

The preterite of dormir is mostly regular, but the third-person forms swap o for u: durmió, durmieron. This o-to-u shift in third person is the hallmark of stem-changing -ir verbs with an o in the stem.

Anoche dormí ocho horas.

Last night I slept for eight hours.

What it is

Dormir's preterite is regular except for one quirk: the third-person forms (él/ella/usted and ellos/ustedes) shift the stem o to u, giving durmió and durmieron. The other forms keep the o (dormí, dormiste, dormimos, dormisteis). Reflexive dormirse follows the same pattern with a reflexive pronoun.

In Anoche dormí ocho horas (Last night I slept for eight hours), dormí marks a single completed sleep with a clear duration. The preterite frames the sleep as one finished event, distinct from dormía (used to sleep / was sleeping).

How to spot it

Look for the o-to-u shift in third person: durmió, durmieron. The other four forms keep the o (dormí, dormiste, dormimos, dormisteis). Reflexive me dormí, te dormiste, se durmió follows the same rule.

Dormí muy bien anoche. — I slept very well last night.
Se durmió en el sofá. — He fell asleep on the couch.
Los niños durmieron toda la noche. — The children slept all night.

The o-to-u rule shows up in many stem-changing -ir verbs (morir → murió, dormir → durmió). It's predictable: an o in the stem of an -ir verb means u in third-person preterite.

Preterite of Dormir Quick Reference

Preterite of dormir, all six forms

Person	Form	Translation
yo	dormí	I slept
tú	dormiste	you slept
él/ella/Ud.	durmió	he, she, you (formal) slept
nosotros	dormimos	we slept
vosotros	dormisteis	you all slept (Spain)
ellos/Uds.	durmieron	they, you all slept

Common Preterite of Dormir Examples in Spanish

Dormir covers everything from a full night's sleep to a quick nap. The preterite frames each sleep as a completed event, often with a clear duration or location.

Last Night's Sleep

Dormí muy bien anoche.: I slept very well last night.
Dormiste mal por el ruido.: You slept poorly because of the noise.
Durmió hasta tarde el sábado.: He slept in late on Saturday.
Dormimos como troncos en el hotel.: We slept like logs at the hotel.
Durmieron en habitaciones separadas.: They slept in separate rooms.

Anoche, esta noche, el sábado, time markers like these anchor the sleep to a specific past night and demand the preterite.

Falling Asleep (dormirse)

Me dormí viendo televisión.: I fell asleep watching TV.
¿Te dormiste muy tarde?: Did you fall asleep very late?
Se durmió en el sofá después de cenar.: He fell asleep on the couch after dinner.
Nos dormimos en el coche durante el viaje.: We fell asleep in the car during the trip.
Se durmieron en plena conversación.: They fell asleep mid-conversation.

Reflexive dormirse marks the moment of falling asleep (vs. dormir = the act of sleeping). The o-to-u rule applies in se durmió, se durmieron.

Naps and Short Sleeps

Dormí una siesta corta después de comer.: I took a short nap after lunch.
Durmió media hora en el avión.: She slept for half an hour on the plane.
Dormimos en el coche por unos minutos.: We slept in the car for a few minutes.
Durmieron una hora antes del concierto.: They slept for an hour before the concert.
¿Dormiste algo durante el vuelo?: Did you sleep at all during the flight?

Whether the sleep lasted 8 hours or 8 minutes, the preterite works as long as it's a completed event with a clear start and end.

Sleeping Through Events

Dormí toda la película.: I slept through the whole movie.
Durmió mientras hablábamos.: He slept while we were talking.
Dormimos durante toda la tormenta.: We slept through the whole storm.
Durmieron a pesar del ruido.: They slept despite the noise.
¿Cómo dormiste con tanto calor?: How did you sleep with so much heat?

Sleeping through or during an event still takes the preterite when the sleep is a completed unit. Pair with durante or mientras to set the context.

How to Form the Preterite of Dormir

o → u in Third-Person Forms

The stem dormir has o, but in the third-person preterite forms it shifts to u: durmió (él/ella/usted) and durmieron (ellos/ellas/ustedes). The other four forms keep the o: dormí, dormiste, dormimos, dormisteis. This o-to-u shift in third person is the defining trait of stem-changing -ir verbs with o.

dormir → o in 1st/2nd person, u in 3rd person: dormí / durmió / dormimos / durmieron.

Same root, just a vowel change in 3rd person.

Only the él/ella and ellos forms shift. The other four stay with dormir's regular o.

Regular Endings, No Accents on Irregulars

The endings are the standard -ir preterite set: -í, -iste, -ió, -imos, -isteis, -ieron. Yo and él/ella forms keep their accents (dormí, durmió), unlike the truly irregular preterites (tuve, puse) that drop accents.

dormí (accent on í), durmió (accent on ó).

Standard accent placement for regular -ir preterites.

Dormir behaves like a regular -ir verb in its endings; only the stem changes.

Reflexive Dormirse Same Pattern

Reflexive dormirse (to fall asleep) uses identical conjugation, with a reflexive pronoun added: me dormí, te dormiste, se durmió, nos dormimos, os dormisteis, se durmieron. The o-to-u shift still applies in third person.

Me dormí. Se durmieron. Nos dormimos.

I fell asleep. They fell asleep. We fell asleep.

Reflexive pronoun first, then the conjugated form. The stem rule doesn't change.

Same Pattern: Morir → Murió

The other common -ir verb with an o stem (morir, to die) follows the exact same rule: morí, moriste, murió, morimos, moristeis, murieron. Once you've learned dormir, you've learned morir, the only o-to-u stem-change pair in this family.

Se murió ayer. Murieron en el accidente.

He died yesterday. They died in the accident.

-ir verb + o in stem = o-to-u in third-person preterite.

Common Mistakes with Preterite of Dormir

Incorrect: Él dormió ocho horas. — He slept for eight hours. (wrong, third-person needs the o-to-u shift)

Correct: Él durmió ocho horas. — He slept for eight hours.

The third-person singular preterite of dormir is durmió, not dormió. The o in the stem flips to u in él/ella/usted and ellos/ellas/ustedes forms.

Incorrect: Yo durmí muy bien anoche. — I slept very well last night. (wrong, only third-person shifts the stem)

Correct: Yo dormí muy bien anoche. — I slept very well last night.

The o-to-u shift only happens in third-person forms (durmió, durmieron). The yo, tú, nosotros, and vosotros forms keep the original o (dormí, dormiste, dormimos, dormisteis).

Incorrect: Dormía siete horas anoche. — I slept seven hours last night. (wrong, imperfect for a single completed sleep)

Correct: Dormí siete horas anoche. — I slept seven hours last night.

A specific completed sleep with a defined duration takes the preterite (dormí). The imperfect (dormía) would describe habitual or ongoing sleep without a specific endpoint, like 'I used to sleep seven hours every night.'

Preterite of Dormir FAQs

What is the preterite of dormir in Spanish?: The preterite of dormir is: dormí, dormiste, durmió, dormimos, dormisteis, durmieron. The third-person forms (durmió, durmieron) shift the stem o to u; all other forms keep the o. The endings are standard -ir preterite endings with regular accents on yo (dormí) and él/ella (durmió).
Why is it durmió instead of dormió?: Dormir belongs to the stem-changing -ir verb family. Verbs with o in the stem shift to u in the third-person preterite forms (durmió, durmieron). This is the same rule that applies to morir (murió, murieron). The other four forms keep the original o.
How is dormir different from dormirse in the preterite?: Dormir means to sleep (the act of sleeping); dormirse means to fall asleep (the moment of transition). Both take identical conjugation, just add the reflexive pronoun: me dormí (I fell asleep) vs. dormí (I slept). The o-to-u stem rule still applies in se durmió, se durmieron.
What other verbs follow the same o-to-u pattern as dormir?: The main verb that shares this exact pattern is morir (to die): morí, moriste, murió, morimos, moristeis, murieron. Both are -ir verbs with o in the stem, and both shift the o to u in third-person preterite forms. Learning dormir gives you morir for free.
How can I learn to use the preterite of dormir naturally?: Dormir appears in any story about sleep, rest, or daily routines, which Parrot's short-form videos surface constantly. Hearing native speakers say dormí, durmió, durmieron in real morning-after conversations locks in the o-to-u shift without explicit drilling. Spaced repetition handles the form recall on the side.