Irregular Verbs: Complete Pattern Reference

Spanish looks intimidating for its irregular verbs, but almost all of them fall into a small number of patterns. Once you learn the patterns, you can predict the conjugation of hundreds of verbs at a glance. This page collects every pattern — stem changes, irregular yo forms, spelling-change families, preterite clans, future stems, irregular participles, and the few verbs that break every rule.

If you're brand new to irregulars, skim this page once and then revisit each section as you need it. The tables are designed to be scanned.

The core insight is this: "irregular" in Spanish usually means "follows a predictable sub-rule rather than the main rule." Only a handful of verbs are truly one-off irregular (ser, ir, estar, haber), and even those are manageable because they're the ones you use most. Everything else follows a family pattern. Learn the pattern once, and you unlock a whole group of verbs.

Stem changes

Stem-changing verbs keep their regular endings but alter the vowel in the stem when it's stressed. There are four families.

e → ie

The stressed e of the stem becomes ie. This happens in every present tense form except nosotros (and vosotros), because those are the forms where the stress lands on the ending, not the stem.

Common members: pensar, empezar, comenzar, cerrar, querer, perder, entender, preferir, sentir, mentir, divertir, despertar, negar, confesar, recomendar, gobernar.

See e → ie stem change.

o → ue

The stressed o becomes ue. Same rule: everywhere except nosotros.

Common members: poder, contar, mostrar, recordar, encontrar, volver, mover, llover, dormir, morir, costar, soñar, almorzar, acostarse.

e → i

Found only in -ir verbs. The stressed e becomes i.

Common members: pedir, servir, repetir, seguir, conseguir, vestir, elegir, medir, reír, sonreír, despedir, corregir.

u → ue

This is a tiny family — one verb, really: jugar. It's the only verb where u becomes ue.

For the full picture see stem changes overview.

Irregular yo forms

A large group of verbs is perfectly regular except in the yo form of the present indicative. They fall into three sub-patterns.

Verbs ending in -go

The yo form adds a g (often replacing a consonant).

Note that tener, venir, and decir also have stem changes (tengo, tienes, tiene...; digo, dices, dice...). Oír adds a y in other forms too (oyes, oye, oyen).

See irregular yo -go.

Verbs ending in -zco

Verbs ending in -cer or -cir preceded by a vowel add -zco in the yo form.

See irregular yo -zco.

Other irregular yo forms

A handful of verbs have unique irregular yo forms that don't fit the -go or -zco patterns.

See irregular yo other.

Spelling-change verbs

These verbs aren't really irregular — they follow the regular rules of Spanish spelling, which require adjustments when a consonant ends up in front of a vowel it doesn't normally pair with.

See spelling changes overview, car-gar-zar, ger-gir, and guir-uir.

Preterite irregulars

The preterite has its own set of irregular families. They share two features: a changed stem and a shared set of endings that are different from the regular preterite endings (note the unstressed -e in yo and -o in él).

The shared irregular preterite endings: -e, -iste, -o, -imos, -ieron (or -eron for j-stems).

u-stem preterites

A group of verbs shifts their stem vowel to u.

See u-stem preterite.

i-stem preterites

Another family shifts to an i stem.

Note that hacer spells its él form as hizo (not hico) to preserve the soft-c sound. See i-stem preterite.

j-stem preterites

A set of verbs with a j in their preterite stem. These take -eron (not -ieron) in the ellos form.

See j-stem preterite.

Ser, ir, dar, ver in the preterite

These don't fit any family. Learn them as their own cluster.

Note that ser and ir have the same preterite forms. Context tells you which verb is meant.

See ser / ir preterite and dar / ver preterite.

Future and conditional irregular stems

A group of verbs uses a contracted infinitive as the stem for the future and conditional. The endings are still regular — only the stem changes. Whichever stem a verb uses in the future is the same stem it uses in the conditional.

See future irregular stems and conditional irregular stems.

Subjunctive irregulars

A useful rule: the present subjunctive is built from the yo form of the present indicative. Take the yo form, drop the -o, add the subjunctive endings.

• tengo → tenga, tengas, tenga, tengamos, tengan
• conozco → conozca, conozcas, conozca, conozcamos, conozcan
• hago → haga, hagas, haga, hagamos, hagan

This means most of the irregular yo forms we just learned produce irregular present subjunctives automatically.

A small set of verbs, however, has truly irregular subjunctives that don't follow from their yo form.

The imperfect subjunctive is built from the third-person plural of the preterite. Drop the -ron, add -ra, -ras, -ra, -ramos, -ran (or the -se variants). So hablaron → hablara, tuvieron → tuviera, dijeron → dijera.

See subjunctive irregulars and imperfect subjunctive irregular.

Irregular past participles

Most past participles are regular (hablar → hablado, comer → comido). But a handful of common verbs use shortened, irregular forms.

See past participle formation.

Fully irregular verbs

Four verbs break most of the patterns. You cannot predict their conjugations — you have to memorize each form directly. Fortunately, they are the four most common verbs in the language, so repetition takes care of it.

Ser — to be (essential, defining)

Ir — to go

Estar — to be (state, location)

Haber — to have (auxiliary, there is/are)

Note the special form hay, used only impersonally (hay muchos libros = "there are many books"). It's a historical fossil — elsewhere, the él form of haber is ha.

See ser, estar, haber for deeper coverage.

Gerund irregulars

Most gerunds are completely regular: hablar → hablando, comer → comiendo, vivir → viviendo. But a few verbs change their stem in the gerund.

A useful rule: whenever a root would produce -iiendo or -iendo between two vowels, the i becomes a y (leyendo, not leiendo). This is a pronunciation-driven change, not an arbitrary irregularity.

See gerund irregular and gerund formation.

Imperfect tense irregulars

The imperfect is the most regular tense in Spanish — there are only three irregular verbs in the entire language for this tense.

Ver is only mildly irregular — it acts as if its infinitive were veer, adding the regular -ía endings to an extra e. Ser and ir are fully irregular.

See imperfect irregular ser, imperfect irregular ir, and imperfect irregular ver.

Everything in one reference table

The tables above are organized by pattern. Here's a lookup index of the common irregular verbs with the patterns they belong to.

Quick learner's checklist

A practical order in which to tackle the irregulars. These are the families with the highest payoff per hour of study.

1. The top four irregulars: ser, ir, estar, haber. You'll use these every minute of every conversation. Memorize all of their forms in present, preterite, imperfect, and subjunctive.
2. The -go yo verbs: tener, venir, hacer, decir, salir, poner, traer. These are the second-most-common irregulars, and they crop up constantly in everyday speech.
3. e→ie and o→ue stem changes: The largest family of pattern verbs. Once you see it, you'll recognize it.
4. Preterite u-stem and j-stem families: Needed to talk about the past in any detail. Tuve, estuve, pude, dije, traje are unavoidable.
5. Future/conditional irregular stems: You can get by without them for a long time using ir a + infinitive, but eventually you want tendré, podré, haré, diré.
6. Subjunctive irregulars: Prioritize the six fully irregular ones (sea, vaya, esté, haya, sepa, dé) — the rest derive from the yo form of the present.
7. Irregular past participles: Memorize the short list — they appear in every compound tense.

Going deeper

• Regular vs irregular verbs — the conceptual overview.
• Stem changes overview
• Spelling changes overview
• Ser / estar / haber
• Preterite u-stem, i-stem, j-stem
• Future irregular stems
• Past participle formation