If you’re learning Spanish, you’ve almost certainly come across conditional sentences: those structures that let you express a condition and its consequence, as in “Si tengo tiempo, te llamo” or “Si hubiera estudiado, habría aprobado“.

Spanish follows very precise rules for these constructions: each type of condition — real, unlikely, impossible in the past — requires a specific combination of moods and verb tenses, and mixing them incorrectly doesn’t just make the sentence sound less natural, it often makes it simply wrong. This is one of the topics that causes the most uncertainty for Spanish learners. The good news is that once you understand the logic behind each structure, the system becomes extremely predictable and consistent.

In this article, we’ll go through all the main oraciones condicionales in Spanish, with concrete examples for each case, so you can recognise and use them with confidence.

1. Real and possible conditions

Let’s start with the simplest and most common case: when the condition is realistic, in the present or the future. Here’s the structure:

Si + presente de indicativo + futuro / presente / imperativo

– Si estudias lo suficiente, aprobarás.
– Si tienes tiempo, hablamos.
– Si llama Javier, avísame.

You’ll recognise this logic straight away, because it works exactly the same way in English: you never say si estudiarás (the equivalent of “if you will study“), just as in English you wouldn’t say “if you will study, you will pass” — you’d say “if you study, you will pass“. The main clause, on the other hand, can be in the future (for a certain outcome), the present (for a habit or an immediate arrangement) or the imperative (for an order or a piece of advice) — again, just as in English.

There’s also an interesting variant for talking about the past: when a condition happened, or may have happened, at an earlier point, the agreement still stays in the indicative.

– Si se quedó hasta el final, será porque se encontraba a gusto.
– Si insistió tanto en ello, diría la verdad.

2. Unlikely or impossible conditions in the present/future

When the condition is hypothetical, unlikely, or completely unreal with respect to the present or future, the pretérito imperfecto de subjuntivo comes into play together with the condicional simple:

Si + pretérito imperfecto de subjuntivo + condicional simple

– Si me encontrara dinero por la calle, te invitaría al mejor restaurante.

Here’s a key difference from English: where English simply uses the past simple after “if” (if I found money on the street, I would invite you to the best restaurant), Spanish requires the subjuntivo mood. It looks similar to the past simple in some verbs, but it’s a genuinely different form, and this is one of the trickiest points for English speakers to get used to.

There’s also a more formal, rather elegant variant, which replaces “si” with “de + infinitivo”:

De + infinitivo + condicional simple

– De encontrarme dinero por la calle, te invitaría al mejor restaurante.

This second form is very common in written Spanish and in more polished contexts, so it’s worth being able to recognise it, even if you’ll use it less than the “si” structure at first.

3. Impossible conditions in the past

This is probably the most complex structure, but also one of the most useful, because it lets you express what could have happened but didn’t — the classic expression of regret. The condition refers to a past action that never took place, so the outcome is equally unreal.

Si + pretérito pluscuamperfecto de subjuntivo + condicional compuesto

– Si hubiera / hubiese visto la señal de prohibido, no habría aparcado aquí.

Here too, the logic diverges from English: you’d say “if I had seen the no-parking sign, I wouldn’t have parked here”, using the past perfect (an indicative form). Spanish, instead, always uses the pretérito pluscuamperfecto de subjuntivo after “si”.

There’s also an alternative with “de + infinitivo compuesto”, which can be followed by either the condicional compuesto or the pretérito pluscuamperfecto de subjuntivo in the main clause:

De + infinitivo compuesto + condicional compuesto / pretérito pluscuamperfecto de subjuntivo

– De haber sabido las consecuencias, no lo habría hecho.
– De haber sabido las consecuencias, no lo hubiera / hubiese hecho.

A useful thing to remember: the pretérito pluscuamperfecto de subjuntivo is always used to express unreal actions in the past, even outside conditional sentences. Think of expressions like ¡Ojalá no hubiera venido! (“If only I hadn’t come!”), where the sense of regret is obvious even without the “si” structure.

4. Colloquial forms: how Spanish speakers actually talk

In everyday speech, Spanish speakers often simplify these structures using more direct, colloquial alternatives. One of the most common is llegar a + infinitivo, followed by the condicional compuesto or the presente de indicativo:

Si + llegar a (in the present) + infinitivo + condicional compuesto / presente de indicativo

– Si lo llego a saber antes, no habría venido.
– Si lo llego a saber antes, no vengo.

And, even more simply, in spontaneous spoken Spanish, you can use the presente de indicativo in both parts of the sentence:

Si + presente de indicativo + presente de indicativo

– Si lo sé antes, no vengo.

These colloquial forms will be very useful for understanding films, TV series and real conversations, where “textbook” grammar often gives way to more practical, immediate solutions.

A mistake to avoid at all costs

There’s one rule with no exceptions: the conditional particle “si” is never combined with the future or the conditional. Sentences like Si será…, Si habrá sido…, Si sería… or Si habría sido… are always incorrect. If you catch yourself writing “si” followed by one of these tenses, that’s your cue to rethink the structure: the verb after “si” should almost always be in the presente de indicativo, the pretérito imperfecto de subjuntivo or the pretérito pluscuamperfecto de subjuntivo — never in the future or the conditional.

5. Expressing the bare minimum condition

Besides “si”, Spanish has other connectors to express the minimum requirement for a result to happen: siempre que, con tal de que and a condición de que. All of them take the subjuntivo, and the choice of tense follows the same logic of probability we’ve seen for “si”:

– Vendré contigo siempre que me acompañes mañana al doctor.
– Con tal de que me dejara en paz, le daría todo lo que me pidiera.
– Habría aceptado las disculpas a condición de que no lo hiciese nunca más.

These expressions are perfect when you want to stress that a certain condition is the one and only requirement for something to happen — much like “provided that” or “as long as” in English.

6. When the condition is the only possible way out

Finally, there are two connectors speakers use to signal that a given condition is the only cause, or the only exception, that could change the outcome: a no ser que and salvo que. Here too, the verb always goes in the subjuntivo.

– No aceptaré hablar con él a no ser que se disculpe.
– Salvo que me mintiera, él no debería estar ahí.

These structures are very useful in more formal or argumentative contexts, when you want to present a single exception to a general rule — the Spanish equivalent of “unless” in English.

7. Why it’s worth mastering conditional sentences

Conditional structures aren’t just a grammar chapter to study and file away: they’re one of the most powerful tools for expressing nuance, hypotheses, wishes and regrets in Spanish. They let you talk about what’s possible, what’s unlikely, and what could have happened but didn’t — situations we run into constantly in real life, from the simple “if you have time, call me” to the more elaborate “if I had known, I wouldn’t have done it”. Mastering these mechanisms will take your Spanish to a noticeably higher level, both written and spoken, and will help you sound far more natural and confident in front of a native speaker.

8. Want to go deeper and put this into practice?

If you’d like to review all the conditional structures we’ve covered today in a clear, organised way, with charts ready for quick reference, take a look at the grammar sheet dedicated to Estructuras condicionales in the Sillabi resources: it’s designed to support you while you study and practise.

And if any of the verb tenses involved still feel unclear, remember that the Sillabi resources also include grammar sheets dedicated to each individual verb tense you need to build these structures, from the pretérito imperfecto de subjuntivo to the condicional compuesto.

And if you want to make the real leap forward — the one that lets you use these structures naturally in a real conversation — check out the It’s up to me! course: a practical, progressive and motivating path designed to help you master the most complex structures in Spanish, conditionals included, with confidence and without stress.

Don’t wait: take the level test today to find out where to start and see just how much your Spanish can improve with the right method.