Ser and Estar both mean: to be.
How do we know which one to use?
Ser: Use “ser” in these situations:
Use “ser” when talking about where someone is from.
1. Yo soy de Nueva York. (I am from New York.)
2. Ellos son de Colombia. (They are from Colombia.)
Use “ser” to describe people’s characteristics.
1. Lorena es guapa. (Lorena is pretty.)
2. Nosotros somos inteligentes. (We are smart.)
Use “ser” to describe someone’s profession.
1. Yo soy una profesora. (I am a teacher.)
2. Paco es un doctor. (Paco is a doctor.)
Use “ser” to give the time and date.
1. El concierto será a las ocho. (The concert will be at eight o'clock.)
2. Son las cinco de la tarde. (It is 5pm)
Estar: Use “estar” in these situations:
Locations:
Use “estar” to describe where someone or something is.
1. Yo estoy en mi casa. (I am at home.)
2. ¿Dónde está el baño? (Where is the bathroom?)
Emotions:
Use “estar” to describe how someone feels.
1. Diego está feliz. (Diogo is happy.)
2. ¿Cómo estás tú? (How are you?)
Ser means = to be
Yo soy (I am)
Nosotros/Nosotras somos (We are)
Tú eres (You are)
Vosotros/ Vosotras sois (You are)
Usted, él, ella es (He/She is)
Ustedes/ellos/ellas son (They are)
Estar means = to be
Yo estoy (I am)
Nosotros/Nosotras estamos (We are)
Tú estás (You are)
Vosotros/ Vosotras estáis (You are)
Usted, él, ella está (He/She is)
Ustedes/ellos/ellas están (They are)