por las DOO-das
Literally, this means 'for the doubts'.
In practice, it means doing something as a precaution, like 'just in case'.
Lleva un paraguas, por las dudas.
B1Take an umbrella, just in case.
Voy a guardar tu número de teléfono, por las dudas.
B1I'm going to save your phone number, just in case.
Aunque el pronóstico dice que hará sol, traje una chaqueta por las dudas.
B2Although the forecast says it will be sunny, I brought a jacket to be on the safe side.
This phrase doesn't have a complex historical story; its origin is quite logical. It's a shortening of a longer idea like 'Hago esto por si acaso existen dudas sobre lo que podría pasar' (I'm doing this in case there are doubts about what might happen). Over time, it was simplified to the very direct 'for the doubts'. It's a practical expression that directly addresses the uncertainty of the future.
Use 'por las dudas' at the end of a sentence to explain why you're taking a precaution. It’s the perfect way to say you're preparing for an uncertain outcome, whether it's bringing a charger when your phone is full or making extra food for a party.
In some countries, especially Argentina, you'll hear this shortened even further to just 'por las' in very informal chat. For example: 'Traje más bebida, por las...' ('I brought more drinks, just in case...').
Mistake: “Thinking 'por las dudas' and 'por si acaso' are completely different or not knowing which one to use.”
Correction: They are very similar and often interchangeable! Both mean 'just in case'. Think of them as regional flavors. 'Por las dudas' is extremely common in the Southern Cone (Argentina, Uruguay), while 'por si acaso' is the more universal version you'll hear everywhere.
Extremely common. This is the default phrase for 'just in case' in everyday speech and is used constantly.
It's understood, but the phrase 'por si acaso' is far more common and is the standard equivalent.
Question 1 of 1
You pack a sweater for a warm day 'por las dudas'. Why are you doing this?
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It leans informal and is very common in everyday conversation. For a formal email or document, the phrase 'por si acaso' is a slightly safer and more standard choice, but 'por las dudas' would still be understood.
