What is the future of ser in Spanish?

Seré, serás, será, seremos, seréis, serán. Regular conjugation: future endings attached to the infinitive ser. Used for predictions about future identity, state, conditions, and for present probability (¿Quién será? = Who could it be?).

What's the difference between seré and voy a ser?

Both mean I will be. Simple future (seré) is slightly more formal and concise; ir a + infinitive (voy a ser) is more conversational. For present probability (it must be), only simple future works: Serán las cinco.

Why does Spanish use the future tense for present probability?

It's a Romance language pattern: the future tense projects uncertainty, so it naturally expresses conjecture about the present. ¿Quién será? literally means who will be? but functionally means who could it be (right now)?

Why does seremos not carry an accent?

Spanish accent rules: words ending in -n, -s, or a vowel are naturally stressed on the second-to-last syllable. Seremos already follows this rule (stress on -re-), so no accent is needed. Other forms (seré, serás, será) end in stressed final syllables, requiring the accent.

How can I master the future of ser?

The future of ser is fully regular: ser + endings. Drill the six forms, then practice in both prediction contexts (Seré médico) and probability contexts (Será fácil = It's probably easy). Parrot's videos surface both uses in natural conversation.

Spanish grammar · Intermediate

Future of Ser: Seré, Serás, Será, Conjugation and Use

Written by Sofia Ramirez, Lead Spanish Curriculum Editor · Reviewed May 2026

The future of ser is regular: seré, serás, será, seremos, seréis, serán. Add future endings (-é, -ás, -á, -emos, -éis, -án) to the infinitive ser. Used for future identity, predictions, and probability.

Mañana seré profesor.

Tomorrow I will be a teacher.

What it is

The future of ser is regular: seré, serás, será, seremos, seréis, serán. Future endings (-é, -ás, -á, -emos, -éis, -án) attach directly to the infinitive ser. Used for future identity, conditions, predictions, and probability about the present.

In Mañana seré profesor (Tomorrow I will be a teacher), seré is the future yo form of ser, predicting a future identity.

How to spot it

Look for seré, serás, será, seremos, serán. All carry an accent (except seremos). Common with future time markers: mañana, el próximo año, dentro de poco.

Será fácil. — It will be easy.
Serán las cinco. — It must be five o'clock. (probability)
Seremos millonarios. — We'll be millionaires.

Future ser (seré) describes future identity / state. Also used for present probability: ¿Quién será? = Who could it be?

Future of Ser Quick Reference

Future of ser, regular

Person	Form	Translation
yo	seré	I will be
tú	serás	you will be
él/ella/Ud.	será	he/she/it will be
nosotros	seremos	we will be
vosotros	seréis	you all will be (Spain)
ellos/ellas/Uds.	serán	they will be

Common Future of Ser Examples in Spanish

Future of ser in real contexts:

Future Identity and Roles

Algún día seré médico.: Some day I'll be a doctor.
Serás un buen padre.: You'll be a good father.
Seremos amigos para siempre.: We'll be friends forever.
Serán los próximos campeones.: They'll be the next champions.
Será un día especial.: It'll be a special day.

Use for predictions about future identities, roles, or states.

Present Probability / Conjecture

¿Qué hora es? Serán las cinco.: What time is it? It must be around five.
¿Quién será?: Who could it be? (at the door)
Será mexicano por el acento.: He must be Mexican from his accent.
Serán unos veinte estudiantes.: There must be about twenty students.
Será verdad lo que dice.: What she's saying must be true.

A major use of future ser is expressing present probability or conjecture. Translates as must be or probably is.

Predictions about Conditions / Weather

Mañana será un día soleado.: Tomorrow will be a sunny day.
Será difícil pero posible.: It will be difficult but possible.
El examen será largo.: The exam will be long.
Serán momentos inolvidables.: They will be unforgettable moments.
Será mejor mañana.: It'll be better tomorrow.

Used to predict conditions, qualities, weather, and characteristics in the future.

Comparison with Ir a + Infinitive

Seré médico. = Voy a ser médico.: I'll be a doctor. = I'm going to be a doctor.
Será fácil. = Va a ser fácil.: It'll be easy. = It's going to be easy.
Serán las cinco. (probability, ir a doesn't work here.): It must be five. (only future ser)
¿Quién será? (only future, ir a doesn't fit): Who could it be? (only future)
Mañana seré feliz. = Mañana voy a ser feliz.: Tomorrow I'll be happy.

Future tense and ir a + infinitive are interchangeable for actual future. Only future tense expresses present probability.

How to Use the Future of Ser

Regular Conjugation: Endings on Infinitive

Future endings (-é, -ás, -á, -emos, -éis, -án) attach to the infinitive ser. No stem change. All forms carry an accent except seremos.

ser + é = seré, ser + ás = serás, ser + á = será.

Predictable, regular pattern.

Infinitive + future endings.

Probability / Conjecture Use

Spanish frequently uses the future tense to express present probability. Será las cinco = It must be five. ¿Quién será? = Who could it be? English uses must / probably for this; Spanish uses the future.

Será verdad = It's probably true. Serán turistas = They must be tourists.

Future tense = present probability.

Future ser = conjecture about present.

Same Stem as Conditional

The future stem (ser-) is the same as the conditional stem. Future endings: -é, -ás, -á, -emos, -éis, -án. Conditional endings: -ía, -ías, -ía, -íamos, -íais, -ían. Learn the stem once, apply two sets of endings.

Future: seré. Conditional: sería.

Same stem, different endings.

Future stem = conditional stem.

Distinguish from Ir + Infinitive

Spanish has two ways to express future: simple future (seré) and ir a + infinitive (voy a ser). Both are correct. Simple future is slightly more formal; ir a + infinitive is more conversational.

Seré profesor. / Voy a ser profesor.

I'll be a teacher. (both work)

Simple future = formal/probability. Ir a = conversational.

Common Mistakes with Future of Ser

Incorrect: Sere profesor. — I'll be a teacher.

Correct: Seré profesor. — I'll be a teacher.

Future yo form carries an accent: seré. Without the accent, the stress shifts incorrectly and changes the meaning.

Incorrect: Voy a ser las cinco. (meant: it must be five) — It must be five o'clock.

Correct: Serán las cinco. — It must be five o'clock.

Ir a + infinitive doesn't work for probability. For present conjecture, use simple future tense: Serán las cinco = It must be (around) five.

Incorrect: Sera fácil mañana. — It'll be easy tomorrow.

Correct: Será fácil mañana. — It'll be easy tomorrow.

All future ser forms (except seremos) carry an accent: será, serás, serán, seréis. Without the accent, the word is misspelled.

Probability with the Future Tense

Present Probability with Future Ser

Future tense ser is commonly used to express probability or conjecture about the present. Translates as must be, probably is, could be.

¿Qué hora es? Serán las nueve.: What time is it? It must be around nine.
¿Quién será?: Who could it be?
Será de tu hermano.: It must be your brother's.

Don't translate this future literally. It's a present probability, not an actual future prediction.

Compare Future for Probability with Deber De

Future for probability is interchangeable with deber de + infinitive (must, indicates probability). Both express conjecture.

Serán las cinco. = Deben de ser las cinco.: It must be around five.
Será verdad. = Debe de ser verdad.: It must be true.
¿Quién será? = ¿Quién debe de ser?: Who could it be?

Future for probability is more concise; deber de is more explicit. Both are correct in conversational Spanish.

Future of Ser FAQs

What is the future of ser in Spanish?: Seré, serás, será, seremos, seréis, serán. Regular conjugation: future endings attached to the infinitive ser. Used for predictions about future identity, state, conditions, and for present probability (¿Quién será? = Who could it be?).
What's the difference between seré and voy a ser?: Both mean I will be. Simple future (seré) is slightly more formal and concise; ir a + infinitive (voy a ser) is more conversational. For present probability (it must be), only simple future works: Serán las cinco.
Why does Spanish use the future tense for present probability?: It's a Romance language pattern: the future tense projects uncertainty, so it naturally expresses conjecture about the present. ¿Quién será? literally means who will be? but functionally means who could it be (right now)?
Why does seremos not carry an accent?: Spanish accent rules: words ending in -n, -s, or a vowel are naturally stressed on the second-to-last syllable. Seremos already follows this rule (stress on -re-), so no accent is needed. Other forms (seré, serás, será) end in stressed final syllables, requiring the accent.
How can I master the future of ser?: The future of ser is fully regular: ser + endings. Drill the six forms, then practice in both prediction contexts (Seré médico) and probability contexts (Será fácil = It's probably easy). Parrot's videos surface both uses in natural conversation.