Learn Hardcore Spanish (Spain): Si me llamas, te respondo en seguida.

Si + present indicative, present indicative / future meaning
- Si me llamas, te respondo en seguida.
- Literally: If you call me, I answer you right away → meaning: If you call me, I’ll answer you right away.

This is standard with si (if), cuando (when), en cuanto (as soon as), etc., when the situation is realistic and possible.

Using the future tense here (Si me llamarás, te responderé) is ungrammatical in Spanish. The future usually appears only in the result clause, and even there, in everyday speech, the present is very common and feels more immediate: te respondo instead of te responderé.

Could I say Si me llamas, te responderé en seguida instead? Is that correct?

Yes, that is correct Spanish, and it sounds perfectly natural.

Difference in nuance:

Si me llamas, te respondo en seguida.
– Very immediate, almost like a promise or a standing policy: If you call, I (always) answer right away.
Si me llamas, te responderé en seguida.
– Slightly more explicitly future-oriented or formal: If you call, I will answer right away.

Both are fine. Using the present in the result clause is just more colloquial and very common in Peninsular Spanish.

Why is it me llamas and not llamas me?

Spanish object pronouns like me, te, lo, la, le, nos, os, los, las, les are clitic pronouns. With a finite (conjugated) verb, they normally go before the verb:

Me llamas – you call me
Te veo – I see you
Lo compro – I buy it

So llamas me is wrong here.

They only go after and attached to the verb in three cases:

Infinitive: llamarme, verte, hacerlo
Gerund: llamándome, viéndote
Affirmative imperative: llámame, mírame, cómpralo

That’s why in a sentence with a normal present tense, it must be Si me llamas…, not Si llamas me…

Does me llamas here mean “you call me (on the phone)” or “you call me (by some name)”?

In this context, it means “you call me (on the phone)”.

Spanish llamar has two common uses:

Llamar por teléfono a alguien – to call someone (on the phone)
- Si me llamas, te respondo en seguida. – If you call me (phone), I’ll answer right away.
Llamar a alguien X – to call someone (by a name), to name someone
- Me llamas “genio” cuando saco buenas notas. – You call me “genius” when I get good grades.

In the sentence you gave, the natural interpretation is the phone meaning; context and the presence of te respondo (“I answer you”) strongly point to the phone-call reading.

Why is it te respondo and not just respondo?

Responder can be used in two main ways:

Responder a alguien – to answer someone (person as indirect object)
- Te respondo = I answer you
  (literally: I answer to-you)
Responder algo – to answer something (thing as direct object)
- Respondo a tu pregunta. – I answer your question.

In everyday speech, when the person is important, Spanish speakers often include the pronoun:

Si me llamas, te respondo en seguida.
– If you call me, I (will) answer you right away.

You could say Si me llamas, respondo en seguida, and it’s still understandable, but it sounds less personal and less typical; te respondo is the natural choice.

What’s the difference between responder and contestar here?

In this context, they’re near-synonyms:

Responder – to respond / answer
Contestar – to answer / reply

You could say:

Si me llamas, te contesto en seguida.

In Peninsular Spanish:

Contestar is extremely common for answering the phone:
- ¡Contesta al teléfono! – Answer the phone!
Responder is a bit more general or formal: responding to a question, an email, a complaint, etc.

But in your sentence, te respondo and te contesto are both natural and correct.

Why is it en seguida and not enseguida? Which is correct?

Both forms are acceptable in modern Spanish:

en seguida – two words
enseguida – one word

According to current usage and dictionaries:

Enseguida (one word) is more common nowadays.
En seguida is still correct but somewhat less frequent.

Meaning is the same: right away, immediately, at once.

So in practice you’ll probably see and hear:

Si me llamas, te respondo enseguida.

Do I have to use a comma after the si clause: Si me llamas, te respondo en seguida?

When the si-clause comes first, the comma is standard and recommended:

Si me llamas, te respondo en seguida.

If you reverse the order, the comma is usually not used:

Te respondo en seguida si me llamas.

So:

[Si-clause first] → normally with comma
[Si-clause second] → normally without comma

Could I change the order to Te respondo en seguida si me llamas? Does the meaning change?

Yes, you can change the order, and the basic meaning stays the same:

Si me llamas, te respondo en seguida.
Te respondo en seguida si me llamas.

The difference is only in emphasis:

First version emphasizes the condition (“if you call me…”).
Second version emphasizes the result/promise (“I’ll answer you right away…”).

Both are natural in Peninsular Spanish.

How would this sentence change if I use the formal usted form instead of tú?

For usted, the verb forms and pronouns change:

Si me llama, le respondo en seguida.

Changes:

llamas → llama (3rd person singular for usted)
te → le (indirect object pronoun for usted in standard Peninsular Spanish)

So:

Tú: Si me llamas, te respondo en seguida.
Usted: Si me llama, le respondo en seguida.

Why is it si without an accent and not sí?

Spanish distinguishes:

si (without accent) = if
- Si me llamas, te respondo… – If you call me, I (will) answer you…
sí (with accent) = yes, or a stressed pronoun in some contexts
- Sí, te respondo en seguida. – Yes, I’ll answer you right away.

In conditional sentences, you always use si without accent.

Why is the indicative used (me llamas / te respondo) instead of the subjunctive? When would I use the subjunctive here?

In Spanish conditionals:

Real / likely condition (present or future):
- Si + present indicative, present or future (or imperative)
- Si me llamas, te respondo en seguida.
- Si vienes, te invito.
The idea is: This is a real, possible situation.
Unreal / hypothetical condition (present or future):
- Si + imperfect subjunctive, conditional
- Si me llamaras, te respondería en seguida.
  – If you called me (but you don’t / it’s unlikely), I would answer you right away.

So:

Si me llamas, te respondo en seguida. – Realistic future: If you do call, I (will) answer.
Si me llamaras, te respondería en seguida. – Hypothetical: If you called (but you probably won’t), I would answer.

In your original sentence, the speaker assumes the condition is realistic, so they use the indicative.