Conditional In Spanish Irregulars | 12 Stems to Know

The Spanish conditional tense uses a small, specific set of about 12 irregular stems, identical to the future tense stems.

You memorize the endings — -ía, -ías, -ía — and you’re ready to say “I would eat” (comería) with confidence. Then you try “I would put” and suddenly the verb poner looks wrong. Ponería? That can’t be right. It isn’t. A handful of common verbs ditch the infinitive and grab a shorter, altered stem before the endings.

The honest answer is a relief: only about a dozen verbs are irregular in the conditional. And if you already know the future tense irregulars, you already know the stems. The conditional just swaps the future endings for -ía‑style endings. So the set is small, predictable, and manageable.

What Are the Conditional Irregular Stems?

Regular conditional verbs take the full infinitive — hablar becomes hablaría, comer becomes comería. Irregular verbs drop or change the final vowel of the infinitive and sometimes insert a -d. For example, caber (to fit) loses its final e to become cabr-; tener (to have) replaces that e with a d to become tendr-.

The endings are identical for all verbs, regular or irregular: -ía for yo, -ías for tú, -ía for él/ella/usted, -íamos for nosotros, -íais for vosotros, -ían for ellos/ellas/ustedes. The only difference is the stem. This uniformity makes the conditional easier than the present tense, where endings change by -ar, -er, and -ir groups.

Spanishdict’s guide to the conditional tense definition provides the full list. Learners often assume that if a verb is irregular in the present (like tener → tengo) it will also be irregular here. That’s a common mistake — irregularity in one tense does not transfer. The conditional irregulars are a closed set that mirrors the future tense exactly.

Three Stem-Shift Patterns

Most irregular stems follow one of three patterns. Some verbs drop the final vowel entirely: caber → cabr-, poder → podr-, querer → querr-, saber → sabr-. Others replace the vowel with -d: poner → pondr-, salir → saldr-, tener → tendr-, valer → valdr-, venir → vendr-. A couple more are unique: decir becomes dir-, and hacer becomes har-.

Why the Future–Conditional Shortcut Works

This connection feels like a cheat code once you see it. The future tense already forces you to learn irregular stems like har- (hacer) and dir- (decir). If you have those down, you already have the conditional stems. The only difference is the ending set: future uses -é, -ás, -á, -emos, -éis, -án; conditional uses -ía, -ías, -ía, -íamos, -íais, -ían. Mentally swap one set of endings for the other.

• Caber → cabr-: “Cabría en la caja” (It would fit in the box). The e drops cleanly.
• Decir → dir-: “Te diría la verdad” (I would tell you the truth). A dramatic shortening from decir to dir-.
• Hacer → har-: “Haría frío mañana” (It would be cold tomorrow). The c disappears entirely.
• Poder → podr-: “Podríamos ir al cine” (We could go to the movies). Drop the e, keep the rest.
• Poner → pondr-: “¿Pondrías la mesa?” (Would you set the table?). The n becomes nd.

Learning these stems as a separate list is recommended by grammar sources because no single rule covers all of them. Collinsdictionary notes that these same stems as future make the conditional a two‑step process: pick the stem, then add -ía endings.

The Full List of 12 Common Irregulars

Spanishdict lists 12 common verbs that are irregular in the conditional. That’s it. Every other verb — even wildly irregular present‑tense verbs like ser or ir — stays perfectly regular.

Notice that haber, saber, and valer are included even though they are less common in everyday conversation. Still, they follow the same pattern and are worth learning for complete accuracy.

How to Practice and Avoid Common Mistakes

The biggest pitfall is assuming present‑tense irregulars apply here. Ser is wildly irregular in the present (soy, eres, es…) but perfectly regular in the conditional: sería, serías, sería. Estar is also regular. Same with ir (iría) and dar (daría). The conditional irregulars are only those 12. Practice by drilling the stems and mixing them with different subjects.

1. Write out the stem for each of the 12 verbs. Cover the table above and produce only the stems: cabr, dir, habr, har, podr, pondr, querr, sabr, saldr, tendr, valdr, vendr.
2. Pair each stem with the six endings. Say or write cabría, cabrías, cabría… for every verb. Focus on the ones that feel unfamiliar, like querría or valdría.
3. Create one sentence per verb. Example: “No cabría en el ascensor” (It wouldn’t fit in the elevator). This fixes the meaning and form together.
4. Compare with future tense. For each verb, write both future and conditional forms side by side. “Haré” / “Haría”, “Diré” / “Diría”. The stem is identical, the endings differ.
5. Test yourself with a timer. Give yourself 60 seconds to generate the yo form of a random irregular. Speed builds automaticity.

Sources like BBC Bitesize emphasize that the endings are uniform, so once you have the stems, you’re done. No additional irregularities appear in the conditional.

Beyond the Basics: Rare Irregulars and Special Cases

Some reference lists include a few additional verbs that are less frequent but still show the same stem changes. For example, the verbs satisfacer (to satisfy) follows hacer → har-, so its conditional is satisfaría. Similarly, contraer (to contract) behaves like traer, but note that traer itself is regular in the conditional (traería). The key is that every verb that is irregular in the conditional is also irregular in the future, and the stem change pattern is consistent across both tenses.

These compound verbs are worth knowing at an intermediate level, but they are simply extensions of the 12‑verb list. The core remains the same: learn the 12 stems, and you can handle any derived verb that uses one of those roots.

The Bottom Line

Conditional irregulars in Spanish are a small, manageable group of about a dozen verbs. Their stems match the future tense exactly, so you only need to learn one set of changes. Drill the stems, practice with different subject endings, and you’ll handle “would” statements in Spanish without hesitation.

For structured review, a certified Spanish teacher (DELE or equivalent) can help reinforce these patterns with targeted exercises at your current proficiency level, whether you are preparing for a DELE exam or aiming for conversational fluency.