Possessive adjectives indicate ownership, relationship, or proximity between a person and a noun. They agree with the noun in number and, in some cases, also in gender, and they usually come before the noun. Their use relates to adjective agreement and to the base form of the adjective in Spanish, which also appears in Adjectives.},{

The most frequent short forms are mi, mis; tu, tus; su, sus; nuestro, nuestra, nuestros and nuestras; vuestro, vuestra, vuestros and vuestras. The forms mi, tu and su do not change for gender, while nuestro and vuestro do change according to the gender and number of the noun. In the plural, all the short forms mark number with mis, tus, sus, nuestros and vuestros.

IdeaIdea	EjemploExample
mi cambia en plural con sustantivos plurales.mi changes in plural with plural nouns.	Mi hermana vive aquí.My sister lives here.
nuestro concuerda en género y número con el sustantivo.our agrees in gender and number with the noun.	Nuestra casa es grande.Our house is big.
vuestros concuerda en género y número con el sustantivo.your (plural) agrees in gender and number with the noun.	Vuestros libros están en la mesa.Your books are on the table.
sus sirve para varias personas o tratamientos.sus is used for several people or forms of address.	Sus perros duermen fuera.Their dogs sleep outside.

Possessive adjectives are usually placed before the noun: my house, your book, our friends. With family members, the singular normally appears without an article: my mother, your brother, his son. In general Spanish, the form vuestro is common in Spain and hardly used in Latin America, where su is preferred.

IdeaIdea	EjemploExample
van antes del sustantivo en uso neutro.They come before the noun in neutral usage.	Mi bolso está en la silla.My bag is on the chair.
los nombres de familia suelen ir sin artículo en singular.Family names usually go without an article in the singular.	Mi madre cocina temprano.My mother cooks early.
vuestro es propio del español peninsular.Vuestro is specific to Peninsular Spanish.	Vuestra clase empieza a las ocho.Your class starts at eight.
en América Latina se prefiere su en ese contexto.In Latin America, su is preferred in that context.	Su clase empieza a las ocho.Your class starts at eight.

The form 'su' can refer to him, her, you (formal), them or you all, so it can sometimes be ambiguous. To avoid confusion, it is often used with an additional noun or pronoun, such as de Juan, de ella or de usted. In colloquial or emphatic registers, an article plus possessive can also appear, such as la casa mía, especially to add emphasis or expressive tone.

IdeaIdea	EjemploExample
su puede ser ambigua sin contexto suficiente.su can be ambiguous without sufficient context.	Su coche está afuera.Your car is outside.
de más nombre aclara la referencia.with an added noun clarifies the reference.	La coche de Juan está afuera.The car of Juan is outside.
de más pronombre aclara el referente.with an added pronoun clarifies the referent.	La idea de ella es clara.The idea of her is clear.
artículo más posesivo puede aportar énfasis o tono coloquial.an article plus possessive can add emphasis or a colloquial tone.	La culpa mía fue llegar tarde.My fault was arriving late.

The possessive adjectives relate to possessive pronouns, but they are not the same form: my house versus mine, your book versus yours. The first accompany the noun and the second replace it, so it is advisable to distinguish both systems for precise use Possessive Pronouns.

IdeaIdea	EjemploExample
el adjetivo posesivo acompaña al sustantivo.the possessive adjective accompanies the noun.	Mi libro está abierto.My book is open.
el pronombre posesivo sustituye al sustantivo.the possessive pronoun replaces the noun.	El mío está abierto.Mine is open.
la forma plena concuerda con el sustantivo sustituido.the full form agrees with the substituted noun.	La tuya es más pequeña.Yours is smaller.
ambos sistemas muestran posesión pero cumplen funciones distintas.both systems show possession but fulfill distinct functions.	Su llave y la suya no significan lo mismo.Her key and hers do not mean the same.

Possessive adjectives form a closed system of ownership that combines invariable forms and agreeing forms. Their usual placement before the noun, the agreement of our and yours, the multifaceted value of su, and the options with de + noun allow expressing possession with precision and naturalness. This structure also supports comparison with Adjective Agreement, Demonstrative Adjectives and Possessive Pronouns.