The zero conditional in Spanish is the simplest member of the conditional family: both clauses sit in the present indicative, and the sentence describes a recurring or always-true situation. Si calientas agua a cien grados, hierve. Si hago deporte, duermo mejor. The si here is not introducing a hypothesis — it's introducing a condition that holds whenever it happens. In English, the same pattern uses if + present + present (if you heat water to 100°C, it boils), and the two languages map cleanly onto each other for this type.
It's tempting to dismiss Type 0 as not really a conditional at all — and some grammars do, lumping it under "habitual sentences" or treating it as a footnote to Type 1. But the pattern shows up constantly in everyday speech, and the choice between Type 0 (general truth) and Type 1 (specific future occasion) is one of the first conditional decisions a learner has to make. So it deserves its own page.
The structure
The skeleton is bare:
| Si-clause | Main clause |
|---|---|
| present indicative | present indicative (or imperative) |
That's the whole pattern. Both halves stay in the present indicative tense, and Spanish doesn't shift anything for the conditional reading. The "conditionality" lives entirely in the si itself.
Si calientas agua a cien grados, hierve.
If you heat water to a hundred degrees, it boils.
Si llueve, me mojo.
If it rains, I get wet.
Si haces ejercicio todos los días, te sientes mejor.
If you exercise every day, you feel better.
The first sentence is a physical truth; the second is a near-tautology used to describe a recurring outcome; the third is a piece of folk wisdom. All three follow the same template.
What Type 0 is for
Type 0 covers four overlapping situations, all of which share the property that the condition isn't a one-off — it holds whenever its conditions are met.
Scientific and natural facts. When a relationship between cause and effect is always true.
Si mezclas amarillo y azul, sale verde.
If you mix yellow and blue, you get green.
Habitual routines (personal habits). A pattern in the speaker's own life that recurs reliably.
Si veo una serie española, siempre la veo en versión original.
If I watch a Spanish series, I always watch it in the original version.
Si voy a casa de mis padres, siempre como demasiado.
If I go to my parents' house, I always eat too much.
General behavioural truths (folk wisdom, rules of thumb). A claim about how people in general tend to behave.
Si tomas café por la noche, luego no duermes bien.
If you have coffee at night, you don't sleep well afterwards.
General advice (imperative as main clause). Type 0 can take an imperative in the main clause when offering advice that applies whenever the condition arises.
Si no entiendes algo, pregunta sin miedo.
If you don't understand something, ask without fear.
Si te duele al hacer ese movimiento, no lo hagas.
If it hurts when you do that movement, don't do it.
The imperative-as-main-clause is on the border between Type 0 and Type 1, and either label works. The thing that makes it Type 0 rather than Type 1 is that the advice applies whenever the condition happens, not on one specific upcoming occasion.
Si vs cuando — the interchangeable cousins
When the condition recurs reliably, si and cuando become near-synonyms in Spanish. Both are natural; the choice is one of nuance.
Si voy a casa de mis padres, siempre como demasiado.
If I go to my parents' house, I always eat too much.
Cuando voy a casa de mis padres, siempre como demasiado.
When/whenever I go to my parents' house, I always eat too much.
The two sentences are nearly identical in meaning. The shading:
- cuando foregrounds the recurring time-frame — "every time I go," with the visits taken for granted as real events.
- si keeps a faint "if-then" reading — "in the event that I go," leaving open the possibility that the visits might not happen.
In peninsular Spanish, cuando is slightly more common when the recurrence is taken as given (cuando me ducho por la mañana, me despierto mejor); si is more natural when the recurrence isn't guaranteed (si me ducho por la mañana, me despierto mejor leaves room for not showering in the morning).
Type 0 vs Type 1 — the boundary
The main thing to pin down when learning Type 0 is when it ends and Type 1 begins. Both use the present indicative in the si-clause; the difference is in the main clause and in the meaning.
| Type 0 | Type 1 | |
|---|---|---|
| Time-frame | recurring / general | specific upcoming occasion |
| Si-clause | present indicative | present indicative |
| Main clause | present indicative | future / ir a / imperative / present |
| English cue | "if/whenever" | "if/in case" |
The clearest contrast is between a present-tense and a future-tense main clause for the same si-clause:
Si llueve, me mojo.
If it rains, I get wet. (Type 0 — general truth)
Si llueve mañana, me mojaré.
If it rains tomorrow, I'll get wet. (Type 1 — specific future occasion)
Adding a time-anchor like mañana, el sábado, esta noche almost always pushes the sentence into Type 1 territory. Adding siempre or normalmente pulls it back to Type 0.
Si veo a Marta, le digo que has llamado.
If I see Marta, I'll tell her you called. (Type 1, near-future — note present indicative in main clause)
Si veo a Marta los lunes, normalmente comemos juntas.
If/whenever I see Marta on Mondays, we usually have lunch together. (Type 0)
The role of si in Type 0
Why does Spanish use si (the "if" of conditionals) for what is essentially a "whenever" relationship? Because the si still introduces a condition — even a habitual condition has to be triggered. Si llueve, me mojo says: in any situation in which the trigger (rain) happens, the outcome (getting wet) follows. The si names the trigger; the main clause names the outcome.
Spanish, like English, doesn't make a sharp grammatical distinction between "every time" and "in any instance where." Both are habitual conditions, and both use the same si + present indicative scaffolding. The difference between si and cuando is stylistic, not categorical.
The si...siempre pattern
A very peninsular flavour of Type 0 puts siempre in the main clause to underscore the recurrence.
Si me invitan a su casa, siempre llevo una botella de vino.
If they invite me to their place, I always take a bottle of wine.
Si Pedro coge el coche, siempre lo deja sin gasolina.
If Pedro takes the car, he always leaves it without petrol.
The siempre doesn't change the grammar, but it makes the "whenever" reading explicit and rules out any one-off interpretation. It's a common conversational move in Spain when telling someone about a chronic habit (often someone else's annoying one).
Other adverbs that pin a sentence into Type 0: normalmente, casi siempre, nunca, en general, por lo general, a veces.
Negative Type 0
Negating either clause works the same way — both halves in the present indicative.
Si no estudias, no apruebas.
If you don't study, you don't pass.
Si no riegas las plantas, se mueren.
If you don't water the plants, they die.
The double negative carries the same meaning as in English: a general claim about what happens when something doesn't happen.
The Spaniard's favourite Type 0: cuando bebes, no conduces
A few Type 0 sentences are so entrenched in Spanish public discourse that they function almost as set phrases. The campaign slogan si bebes, no conduzcas (don't drink and drive) is the most famous, though that version uses an imperative; the indicative version si bebes, no conduces lives in safety pamphlets and parenting advice. Notice the use of the tú form throughout — Type 0 in Spain heavily prefers tú even in public advice, because the indefinite "you" reading sounds more natural with tú than with the formal usted.
Si bebes alcohol, no conduces nunca. Es así de sencillo.
If you drink, you never drive. It's that simple.
This generic-tú register is the standard for Type 0 in Spain and is itself a small piece of peninsular grammar worth internalising.
Common Mistakes
❌ Si calentarás agua a cien grados, hierve.
Wrong — the si-clause never takes the future. Even for general truths, present indicative is the only option.
✅ Si calientas agua a cien grados, hierve.
If you heat water to a hundred degrees, it boils.
❌ Si haga ejercicio todos los días, me siento mejor.
Wrong — the si-clause doesn't take the present subjunctive. Use the present indicative.
✅ Si hago ejercicio todos los días, me siento mejor.
If I exercise every day, I feel better.
❌ Si llueve, me mojaría.
Wrong — for a general truth, both clauses are in the present indicative. The conditional 'me mojaría' belongs in Type 2 (hypothetical) and would also need 'si lloviera' in the si-clause.
✅ Si llueve, me mojo. / Si lloviera, me mojaría.
If it rains, I get wet. / If it rained (hypothetically), I'd get wet.
❌ Si tomara café por la noche, luego no duermo.
Wrong — mixing imperfect subjunctive in the si-clause with present indicative in the main clause. For a habitual truth, keep both halves in the present indicative.
✅ Si tomo café por la noche, luego no duermo.
If I have coffee at night, I can't sleep afterwards.
❌ Cuando voy a casa de mis padres, siempre comeré demasiado.
Wrong — the 'cuando'-version of Type 0 also keeps both clauses in the present indicative. The future 'comeré' is appropriate for a one-off upcoming visit, not a habit.
✅ Cuando voy a casa de mis padres, siempre como demasiado.
Whenever I go to my parents' house, I always eat too much.
Key takeaways
- Type 0 describes general truths, habitual routines, scientific facts, and generic advice. Both clauses sit in the present indicative.
- The si in Type 0 is closer to whenever than to if. If "whenever" fits the English, you're in Type 0.
- Si and cuando are nearly interchangeable for habitual conditions in peninsular Spanish. Cuando foregrounds the recurring time-frame; si keeps a faint "if-then" reading.
- The main clause can also be an imperative (advice that applies whenever the condition arises).
- Adding a future-time adverb like mañana usually pushes the sentence into Type 1; adding siempre/normalmente keeps it firmly in Type 0.
Now practice Spanish
Reading grammar gets you part of the way. The exercises are where it sticks — free, no signup needed.
Start learning Spanish→Related Topics
- Oraciones condicionales: guía completaB1 — A full reference for Spanish conditional sentences — the four classical types plus mixed conditionals, organised by how real the speaker considers the condition: factual, real-future, hypothetical, or counterfactual.
- Condicionales tipo 1: real futuroA2 — Spanish Type 1 conditionals describe a real future possibility. The 'si'-clause goes in the present indicative; the main clause can be future, 'ir a' + infinitive, imperative, or present indicative.
- Presente de indicativo: verbos regulares en -arA1 — The six present-indicative endings for regular -ar verbs in peninsular Spanish, including the all-important vosotros form habláis.
- Subjuntivo en cláusulas temporalesB1 — After cuando, mientras, en cuanto, tan pronto como and hasta que with future reference, Spanish uses the subjunctive — not the present or the future indicative. Antes de que always takes subjunctive; después de que is variable but strongly subjunctive in Spain.