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Main differences between ser and estar:
- Ser is mainly used to express permanent conditions, whereas estar is used to express transitory states:
Juan es inquieto (Juan is always like that).
Juan está inquieto (Juan is not always like that, but he is now for some reason).
- Ser is used when something has a quality it is expected to have, whereas estar is used when something has an unexpected quality:
La abuela de Juan es joven (she is a young grandmother).
La abuela de Juan está muy joven para tener 80 años (she looks young for her age).
- Ser is used in the passive voice when a process is implied, whereas estar is used when a state is implied:
La puerta fue cerrada por el viento (a process in which the door closes is referenced).
La puerta está cerrada (the door is just closed).
- La puerta estuvo cerrada* (the door, in some time, was close).
- When talking about food, ser is used to talk about the appearance and estar is used to talk about the taste:
Las tartas que hace Juan son espectaculares (they look impressive).
Las tartas que hace Juan están espectaculares (they may not look impressive but the taste is incredibly good).
Las bayas de enebro son malas (they are bad for your health).
Las bayas de enebro están malas (they taste horribly).
Exception: when you want to say that the taste of something is always the same, regardless of how it is prepared:
La carne de ternera es deliciosa (it always tastes good).
La carne de ternera está deliciosa (this particular beef tastes good).
- Both ser and estar can be used to ask the price, but ser will be used with the interrogative form cuánto to be informed about the final or total price just before paying, while estar will be used with the interrogative form a cuánto to be informed about the current price of an individual item before making the decision whether to buy it or not:
¿A cuánto está el kilo de naranjas?
A un euro.
(After buying three kilos of oranges:) ¿Cuánto es?
Son tres euros.
When to use ser:
- To introduce yourself or someone else:
¡Hola, soy Carlos!
Ese es Pepe.
- To talk about relationships:
Juan es mi hermano.
Paco era mi jefe.
María es la novia de Isabel.
El partido de baloncesto será en el estadio.
La reunión fue en la sala 3.
Son las tres menos cuarto.
Eran las cinco y media cuando salí de casa.
Hoy es jueves.
Ayer fue 30 de mayo.
- To talk about occupations or procedences:
Yo soy pintor.
Mi hermana era ingeniera pero ahora es directora de un hotel.
Estoy estudiando para ser arquitecto.
Yo soy sevillano.
Juan es de Granada.
When to use estar:
- Before gerunds to form continuous tenses:
Estoy escribiendo una respuesta para esta pregunta.
Estábamos cruzando el puente cuando nos asaltó un ladrón.
Los jugadores están en el estadio.
El pastel estaba sobre la mesa.
Fulano está muerto.
El vaso está roto.
- To talk about dates or seasons using the first person plural:
¿A qué día estamos hoy?
Ya estamos en primavera.
- To talk about the very near future:
Estaba por llegar cuando supo que la fiesta se había cancelado.
Estoy a punto de empezar a comer. ¿Puedes llamar más tarde?
- To express how you (or someone else) feel:
-¿Cómo estás? -Estoy bien, gracias.
Juan estaba triste esta mañana, no sé qué le pasaba.
Idiomatic expressions using ser or estar:
One of the most challenging aspects of any language is making sense of idiomatic expressions, that are common knowledge in the community through continuous usage, but may defy the accepted rules of the language, rendering them nonsensical when attempting a literal translation.
The best hope in this cases is finding an equivalent idiomatic expression on the destination language, (probably just as nonsensical) or explaining the reason or situation in which such expressions make sense.
The verbs ser and estar being central to the Spanish language are part of many such expressions, however, in the following examples, the permanency or transitiveness, respectively, are the central theme of the Mexican phrase:
Estar como agua para chocolate
The equivalent english idiom is To be mad as a hornet
Here, a person experiences sudden anger; like the boiling water required on for preparing the traditional hot cocoa beverage. However the transitive nature of this mood is stressed and reassured through the reference to the beverage: it has too cool down in order to be enjoyed, just as our enraged subject will implicitly return to his implied sweet or mild self. Only through the temporary nature of the verb estar can we convey such a concept in so few words.
¿Eres? ¿O te haces?
The equivalent english Idiom is Are you for real? or are you just playing dumb?
This puzzling but powerful expression is very typical, especially when dealing with distracted kids. It leaves out an implicit adjective, which is universally understood within the context of this phrase: Eres tonto? o solo the haces pasar por tonto? the phrase is a harsh coming to terms with someone who may be playing coy by pretending to not understand. However paradoxically, leaving out whatever implied negative adjective we may want to attach to the question (it works in a multitude of contexts) renders the phrase that much stronger, implying we know better than that person who is pretending not to understand. Here, the permanent nature of being a fool, rather than playing one is used as an incentive to motivate compliance.
