When To Use Tu And Su In Spanish? | Clean Up Confusion

Tú is “you,” tu is “your” before a noun, and su is “his/her/their” or formal “your,” so context tells you the owner.

These short words show up everywhere: texts, captions, school writing, work emails. That frequency is why small slips stand out. One accent changes the word’s job, and su can point to several different owners. On a screen, a reader can’t hear your tone, so clarity matters even more.

The good news: you don’t need long grammar rules. You need a handful of checks you can run fast, plus a few rewrite patterns that remove doubt when su could mean more than one thing. That’s what you’ll get below.

The Three Roles Behind Tú, Tu, And Su

Pick the form by its role in the sentence. Role first, spelling second.

Tú: A Subject Or Stressed Pronoun

Tú (with an accent) is a pronoun. It stands for “you” as the person being spoken to. Most of the time it’s the subject of a verb.

• Tú llegas temprano.
• Tú pagas hoy.
• Si tú quieres, vamos.

You’ll also see tú after some prepositions when Spanish needs a stressed form, but note that “for you” is para ti, not para tú. That difference is separate from the tú/tu spelling choice.

Tu: A Possessive Determiner Before A Noun

Tu (no accent) works like “your” before a noun. It points to ownership, relation, or association tied to the person you’re talking to.

• Tu teléfono está aquí.
• Tu hermano llega tarde.
• Tus llaves están en la mesa.

Quick cue: if a noun follows right after, tu/tus is the usual choice.

Su: A Possessive That Can Mean “His, Her, Their,” Or Formal “Your”

Su (and sus) is possessive too, but it does not lock onto one single person the way tu does. It can mean “of him,” “of her,” “of them,” “of you (formal),” or “of you all (formal).” RAE’s grammar section on possessives notes these multiple readings tied to su and suyo.

So su casa can be “his house,” “her house,” “their house,” or “your house” (to usted/ustedes). If the owner is obvious in your conversation, su is fine. If not, you’ll want a rewrite that names the owner.

Why Tú Has An Accent And Tu Doesn’t

Spanish normally does not put accents on one-syllable words. Tú is a famous exception because Spanish uses a special spelling accent to separate two words that look the same but do different jobs in a sentence. RAE spells out that tú (pronoun) keeps the accent to avoid confusion with tu (possessive). RAE’s Diccionario panhispánico de dudas entry for “tú” gives the rule and examples.

If your keyboard makes accents annoying, you still want to learn them. In school, they’re graded. In work writing, they signal care. In chat, they prevent mix-ups like “Tu puedes” (which reads like “Your can”).

When To Use Tu And Su In Spanish? The Fast Decision Checks

When you’re writing quickly, run these checks. They take seconds.

Check 1: Swap In “You” Or “Your” In English

If the meaning is “you,” choose tú. If the meaning is “your,” choose tu.

• “You are late.” → Tú llegas tarde.
• “Your keys.” → Tus llaves.

Check 2: Look At The Next Word

If a noun follows right away, tu/tus or su/sus is in play. If a verb follows and you’re naming the doer, tú is the usual pick.

• Tu café está listo.
• Tú sabes la verdad.

Check 3: Ask “Whose?” Out Loud For Su

Pause and ask “Whose?” If more than one owner makes sense, your reader may pause too. When that pause would be a problem, rewrite the line to name the owner.

RAE notes that forms like su can match “usted,” “ustedes,” or third person owners, so the same word can point to different people. RAE’s “El buen uso del español” section on possessives gives an example such as con su permiso and lists the possible owners.

Using Tu And Su In Spanish In Real Sentences

Here are patterns you’ll write all the time. The goal is a sentence that reads cleanly the first time.

Pattern A: Tú + Verb

• Tú trabajas hoy.
• Tú puedes entrar.
• Tú no quieres café.

Pattern B: Tu + Noun

• Tu mochila pesa mucho.
• Tu opinión cuenta.
• Tus amigos llegan mañana.

Pattern C: Su/Sus + Noun

Use su when the owner is not the informal “you.” It might be a third person, or it might be polite “you” in the usted system. This overlap is normal Spanish, yet it can confuse readers when context is thin.

• Su hijo estudia medicina.
• Sus libros están en la mesa.
• Gracias por su tiempo. (formal)

When you can’t rely on context, Spanish often switches to de + name or de + pronoun: el libro de ella, la casa de usted, los zapatos de ellos.

Form	What It Means	Sentence Model
tú	“you” (informal)	Tú llegas tarde.
tu	“your” before a singular noun	Tu casa es grande.
tus	“your” before a plural noun	Tus fotos están aquí.
su	“his/her/your formal/their” before a singular noun	Su coche está afuera.
sus	Same as su, with a plural noun	Sus ideas son claras.
suyo/suya	Possessive pronoun (singular)	El abrigo es suyo.
suyos/suyas	Possessive pronoun (plural)	Las llaves son suyas.
tuyo/tuya	“yours” used as a pronoun	La culpa es tuya.
tuyos/tuyas	Plural of tuyo/tuya	Esas ideas son tuyas.

Su Vs. Tu In Formal And Informal Address

This is where many learners get stuck: “Why does su sometimes mean ‘your’?” The answer is the usted/ustedes system. Spanish often uses third-person verb forms for polite “you,” and the possessive follows that pattern.

Informal “You” Uses Tu/Tus

• ¿Dónde está tu recibo?
• Me gusta tu idea.

Formal “You” Can Use Su/Sus

• ¿Dónde está su recibo? (to usted)
• Adjuntamos sus documentos. (to ustedes)

When Formal “Su” Might Confuse The Reader

If the message also mentions another person, su can look like it points to that third person. In that case, de usted or de ustedes can be cleaner than su.

Where People Slip Up And How To Fix It

Most mistakes come from speed. Use these fixes and you’ll clean up the errors that show up most often.

Slip 1: Writing “Tu” As A Subject

Wrong: Tu eres mi amigo.
Right: Tú eres mi amigo.

Slip 2: Writing “Tú” Before A Noun

Wrong: Tú casa es bonita.
Right: Tu casa es bonita.

Slip 3: Letting “Su” Stay Vague

In speech, tone and context often clear things up. In writing, your reader has less to work with. When su could point to two people in the same scene, rewrite.

• Vague: Hablé con Ana sobre su proyecto.
• Clear: Hablé con Ana sobre el proyecto de Luis.
• Clear: Hablé con Ana sobre el proyecto de ella.

Slip 4: Mixing “Su” With “Tu” In The Same Line

This can be grammatical, yet it can feel like a sudden switch if the reader loses track of who owns what.

• Trae tu pasaporte y su copia. (Whose copy?)
• Trae tu pasaporte y la copia del pasaporte.

How To Make “Su” Clear Without Sounding Stiff

You don’t need to avoid su. You just need a couple of moves that keep the meaning stable when the context is thin.

Use “De + Name” When Two Owners Are Present

• El bolso de Marta está en la silla.
• La tarea de Juan ya está lista.

Use “De Él/De Ella/De Ellos” When The Owner Is Not Named

• Su respuesta no llegó. → La respuesta de él no llegó.
• Su casa queda lejos. → La casa de ella queda lejos.

Use “De Usted/De Ustedes” In Formal Writing When Needed

• Su solicitud fue recibida. → La solicitud de usted fue recibida.
• Sus documentos están listos. → Los documentos de ustedes están listos.

When “Su” Feels Unclear	Clear Rewrite	Why It Works
Two people appear close together	Use de + name	Names the owner
Owner is “usted” in a formal email	Use de usted	Stops polite/third-person overlap
Owner is “ustedes” in a notice	Use de ustedes	Stops the “their/your” blur
Owner is known but not named	Use de él/de ella	Makes the owner explicit
Object belongs to a group	Use de ellos/de ellas	Signals plural owners
You mean informal “your”	Use tu/tus	Matches informal address
You mean “yours” as a pronoun	Use tuyo/tuya	Moves possession off the noun

Mini Practice: Choose Tú, Tu, Or Su

Try these in your head. If you want, copy the list into a note app and fill it in. Then check your answers by running the three checks above.

1. ____ eres mi profesor.
2. ¿Dónde está ____ chaqueta?
3. ____ amigos llegan tarde.
4. Gracias por ____ llamada. (formal)
5. ____ sabes la respuesta.
6. Voy a ____ casa después.
7. Hablé con Laura sobre ____ examen. (Is it Laura’s or someone else’s?)
8. ¿Me prestas ____ lápiz?
9. El coche es ____. (possessive pronoun)
10. Sus llaves están aquí, señor. (Now rewrite it with de usted.)

A Simple Self-Check Before You Hit Send

1. Mark each tu/tú. If it replaces “you,” add the accent. If it sits right before a noun, leave it without the accent.
2. Mark each su/sus. Ask “Whose?” If two owners could fit, swap in de + name or de él/de ella/de usted.
3. Read the line out loud once. If you stumble, rewrite it.

Fundéu explains tilde diacrítica as a spelling mark used to distinguish same-spelled words with different roles. Fundéu’s note on tilde diacrítica gives a clear definition.