The main rule
Pick the possessive by the owner (yo, tú, él...), then make it agree with the thing: one or several (mi casa, mis casas). Only nuestro and vuestro also change for gender: nuestro piso, nuestra casa. Never match the possessive to the owner's number or gender: Ana has two cats, so sus gatos (one owner, several cats).
The forms
| Owner | One thing | Several things |
|---|---|---|
| yo | mi libro, mi casa | mis libros, mis casas |
| tú | tu libro, tu casa | tus libros, tus casas |
| él, ella, usted | su libro, su casa | sus libros, sus casas |
| nosotros, nosotras | nuestro libro, nuestra casa | nuestros libros, nuestras casas |
| vosotros, vosotras (Spain) | vuestro libro, vuestra casa | vuestros libros, vuestras casas |
| ellos, ellas, ustedes | su libro, su casa | sus libros, sus casas |
English marks the owner: his, her, its, their. Spanish marks the thing. Because of this, su and sus mean "his", "her", "its", "their" and the formal "your" all at once, and the context decides: Ana tiene dos gatos. Sus gatos son negros. If it is unclear, speakers name the owner with de instead: la casa de Ana, la casa de ellos. English also has no plural "my", so the plural thing is a trap: "my books" is mis libros, never *mi libros. And "their house" is su casa, not *sus casa, even though there are several owners. Finally, English "your" is one word, but Spanish has four forms: tu / tus for one friend, su / sus for usted and ustedes, and vuestro for vosotros.
Examples
- Mi hermano vive en Madrid. My brother lives in Madrid.
- Mis padres tienen un perro. My parents have a dog.
- Tú tienes tu mochila. You have your backpack.
- ¿Dónde están tus llaves, Pablo? Where are your keys, Pablo?
- Ana tiene dos hermanos. Sus hermanos son altos. Ana has two brothers. Her brothers are tall.
- Ana y Luis tienen una casa. Su casa es grande. Ana and Luis have a house. Their house is big.
- ¿Es su maleta, señora? Is this your suitcase, madam?
- Nuestra casa está en Sevilla. Our house is in Seville.
- Nuestros abuelos viven en Lviv. Our grandparents live in Lviv.
- ¿Dónde está vuestro piso? Where is your flat? (in Spain, to two friends)
Mi, tu, su: only the number changes
These three have one form for masculine and feminine: mi perro, mi casa. Add -s for plural things: mis perros, mis casas. The number of the owner never matters. A woman says mi padre, and a man says mi madre. When you talk about Ana and her two cats, you say sus gatos; about Ana and Luis and their one house, su casa.
Nuestro and vuestro: gender and number
These two have four forms and agree with the noun in gender and number, like an adjective: nuestro coche, nuestra bicicleta, nuestros primos, nuestras hijas. The speaker's gender is irrelevant: a woman still says nuestro piso, because piso is masculine. Vuestro is used in Spain, for "you" with several friends (vosotros: tenéis, vivís). In Latin America, people say su / sus for the same idea (ustedes).
Su for usted, tu for tú
With a friend, a classmate or a child you say tú and tu: ¿Tienes tu libro? With an older stranger, a clerk or a client you say usted and su: ¿Es su maleta, señor? Do not mix them: tu is informal, su is formal.
Tu or tú?
The possessive tu has no accent. The pronoun tú (you) has one: Tú tienes tu libro. The same applies to mi (my) and mí (me, after a preposition): mi casa, never *mí casa.
A quick check
Look at the noun first: one or several, and for nuestro and vuestro, masculine or feminine. Then choose the person. With su, ask who the owner is in the sentence before it.
Typical mistakes
Mi libros están aquí.Mis libros están aquí. The books are plural, so the possessive is plural too.Mis casa es grande.Mi casa es grande. One house, so mi, not mis.Sus casa es bonita.Su casa es bonita. Su follows the thing: one house, so su, whatever the number of owners.Su libros son nuevos.Sus libros son nuevos. Several books need sus.Nuestro casa es vieja.Nuestra casa es vieja. Casa is feminine, so nuestra.Nuestra hijos viven en Lviv.Nuestros hijos viven en Lviv. Hijos is masculine plural, so nuestros.Tú libro está aquí.Tu libro está aquí. The possessive has no accent.Mí casa es pequeña.Mi casa es pequeña. Mi (my) has no accent; mí means "me".
Common questions
What does su mean in Spanish?
Su means his, her, its, their, and your when you speak to someone as usted or to a group as ustedes. The context shows whose it is, and the plural is sus for several things.
When do I use mis and when mi?
Use mi with one thing (mi casa) and mis with several (mis casas). The number of the thing decides, not the number of owners.
Is it tu or tú?
Tu without an accent is the possessive (tu casa). Tú with an accent is the pronoun "you" (Tú vives aquí).
Do nuestro and vuestro change for gender?
Yes, they have four forms: nuestro, nuestra, nuestros, nuestras. Mi, tu and su change only for number.
How do I say "our" if I am a woman?
Look at the thing, not at yourself: nuestro piso, nuestra casa. The speaker's gender does not matter.
What are mío, tuyo and suyo?
They are another set of possessives, used after the noun or alone. They are learnt later; for now use mi, tu and su before the noun.