How to Say "unreliable" in Spanish
The Spanish word for “unreliable” is “informal” — B1 level.
English → SpanishB1
adjectiveB1
referring to a person who doesn't keep their word
Examples
No confíes en él para el proyecto; es muy informal.
Don't trust him with the project; he is very unreliable.
Siento haber sido tan informal con nuestra cita.
I'm sorry for being so flaky with our date.
Es un trabajador informal y siempre llega tarde.
He is an unreliable worker and always arrives late.
Using 'Ser' vs 'Estar'
Use 'ser' with this meaning because you are describing a person's character trait or habit.
The False Friend Trap
Mistake: “English speakers often only think this means 'not formal'.”
Correction: In Spanish, calling someone 'informal' is a criticism of their character, meaning they don't keep promises.
Related Translations
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