Ser conjugation in Spanish
ser — to be (essential / identity) · participle sido · gerund siendo
Ser is one of the two Spanish verbs meaning “to be”. It is irregular in almost every tense, so it is worth learning the tables below by heart — ser appears in some of the most common sentences you will ever say in Spanish.
Tables show Mexican Spanish: ustedes is the plural "you" (same forms as ellos/ellas). In Spain you'll also hear vosotros — see the variants guide for those forms.
ser conjugation tables
Present
| Pronoun | ser |
|---|---|
| yo | soy |
| tú | eres |
| él/ella/usted | es |
| nosotros | somos |
| ellos/ellas/ustedes | son |
Preterite
| Pronoun | ser |
|---|---|
| yo | fui |
| tú | fuiste |
| él/ella/usted | fue |
| nosotros | fuimos |
| ellos/ellas/ustedes | fueron |
Imperfect
| Pronoun | ser |
|---|---|
| yo | era |
| tú | eras |
| él/ella/usted | era |
| nosotros | éramos |
| ellos/ellas/ustedes | eran |
Future
| Pronoun | ser |
|---|---|
| yo | seré |
| tú | serás |
| él/ella/usted | será |
| nosotros | seremos |
| ellos/ellas/ustedes | serán |
Conditional
| Pronoun | ser |
|---|---|
| yo | sería |
| tú | serías |
| él/ella/usted | sería |
| nosotros | seríamos |
| ellos/ellas/ustedes | serían |
Present subjunctive
| Pronoun | ser |
|---|---|
| yo | sea |
| tú | seas |
| él/ella/usted | sea |
| nosotros | seamos |
| ellos/ellas/ustedes | sean |
Imperfect subjunctive
| Pronoun | ser |
|---|---|
| yo | fuera |
| tú | fueras |
| él/ella/usted | fuera |
| nosotros | fuéramos |
| ellos/ellas/ustedes | fueran |
Imperative (affirmative)
| Pronoun | ser |
|---|---|
| yo | — |
| tú | sé |
| él/ella/usted | sea |
| nosotros | seamos |
| ellos/ellas/ustedes | sean |
How to use ser
When to use ser
Use ser for things you treat as defining: identity (soy profesora), origin (es de México), nationality, profession, material, possession, and clock time (son las tres).
Ser vs estar in one line
Ser describes what something is; estar describes how or where it is right now. Soy feliz = I'm a happy person. Estoy feliz = I'm happy at the moment.
Watch out for fui
The preterite of ser (fui, fuiste, fue…) is identical to the preterite of ir (to go). Context decides: fui médico = I was a doctor; fui a Madrid = I went to Madrid.
ser conjugation FAQ
How do you conjugate ser in the present tense?
Soy, eres, es, somos, sois, son.
Is ser regular or irregular?
Ser is highly irregular: the present, preterite and imperfect stems are all different (soy, fui, era).
What is the difference between ser and estar?
Ser is used for essential qualities such as identity, origin and profession; estar is used for states, locations and moods.
Other full verb guides
Related free Spanish guides
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