Ever wonder why Italians say “mia sorella” but “il mio libro”? Possessive adjectives in Italian look simple, but the article and those family exceptions can be confusing. In this post, you’ll learn the core rules, see lots of everyday examples, and practice with quick exercises so you can use mio, tuo, suo, nostro, vostro, loro confidently in real life.

Meet the Italian possessives

Italian possessive adjectives show ownership. They agree with the thing possessed (the noun), not with the person who owns it.

• io → mio, mia, miei, mie
• tu → tuo, tua, tuoi, tue
• lui/lei → suo, sua, suoi, sue
• noi → nostro, nostra, nostri, nostre
• voi → vostro, vostra, vostri, vostre
• loro → loro (invariable)

Notice how the endings change for masculine/feminine and singular/plural. “Mio” changes because the noun changes.

The article + possessive: the famous rule

In most cases, Italian uses the definite article before a possessive adjective: il mio libro, la tua borsa, i suoi amici, le nostre foto.

There’s a key exception: with singular family members, you normally drop the article: mia sorella, tuo padre, suo zio, nostra nonna. However, loro always keeps the article: il loro padre, la loro sorella.

If the family noun is plural (i miei genitori) or is modified by an adjective (il mio caro fratello), you use the article.

Marta cerca le chiavi.

fratello studia medicina.

il mio padre → mio padre Drop the article with singular family members (except with loro).

Plurals and modified family members

When talking about multiple family members, use the article: i miei genitori, le sue sorelle. If you add an adjective, use the article even in the singular: il mio caro zio, la tua grande famiglia.

This mirrors how Italian packs information: the article helps structure the phrase when there’s extra detail or plurality.

I professori sono gentili.

Suo: his, her, or your (formal)?

“Suo” can mean his, her, or your (formal Lei). Context usually tells you which. If it’s unclear, Italian often clarifies with a name or with di + noun/pronoun: il libro di Marco, il gatto di lei (more formal, less common than using a name).

In formal writing you may see Suo/Sua with a capital S to show respect to Lei: Il Suo documento, per favore.

Real-life phrases: casa, scuola, ufficio

Some places don’t need a possessive, because the default meaning is “my/the usual”:

• Vado a casa. (I’m going home.)
• Sono a scuola/in ufficio. (I’m at school/at the office.)

If you want to specify whose, add the possessive—often after the noun in everyday speech:

• Vado a casa mia / tua / sua.
• Siamo a casa dei miei. (We’re at my parents’ place.)

Putting the possessive after the noun (casa mia) is common and natural, especially with familiar places.

la mia sorella → mia sorella Drop the article with singular family members. la mia amici → i miei amici Amici is masculine plural. Match article and possessive: i miei. i sua libri → i suoi libri Suoi agrees with libri (masc. plural).

Quick recap

• Possessives agree with the noun: mio/mia/miei/mie; tuo/tua/tuoi/tue; suo/sua/suoi/sue; nostro/nostra/nostri/nostre; vostro/vostra/vostri/vostre; loro.
• Use the article before possessives, except with singular family members (mia sorella) — but loro always takes the article (il loro padre).
• Suo can mean his/her/your (formal); clarify with a name or di + pronoun if needed.
• After-noun position is common: casa mia.

Try this: write three sentences about your family and your things. For example: “Mio padre lavora in banca. La mia bici è rossa. A cena vado a casa dei miei.” Share them with a friend and check the articles and endings!

Bravo! Keep noticing how Italians match the possessive to the noun—and you’ll sound more natural every day.