Age is seen as a possession in Spanish, like something you have, rather than something that describes a personal trait. Since you will continue to get older, age isn't a 'permanent' trait that we would apply the verb 'ser' to. Plus, age is not the only expression that uses "tener" instead of "ser". Other examples are: tener hambre/sed (to be hungry/thirsty), tener sueño (to be sleepy), tener frío/calor (to be cold/hot), tener suerte (to be lucky) among others.
Why do we use "tener" when referring to age instead of "ser"?
5 Answers By Expert Tutors
In Spanish, when we talk about age, we use the verb tener (“to have”), not ser (“to be”), because of how the concept of age is expressed.
- In English, we say: “I am 20 years old.” (using to be).
- In Spanish, we say: “Tengo 20 años.” (literally: “I have 20 years.”).
The difference is that Spanish thinks of age as something you possess (like an attribute you have), not something you are.
So instead of describing age as part of your identity (ser), Spanish treats it like a characteristic or condition that you “have” (tener).

Elizabeth R. answered 06/25/25
Experienced AP Spanish Tutor
Because things don't translate perfectly from one language to another. When you ask someone their age in Spanish you're REALLY asking them "how many years do you have?" This is why this question uses tener (to have) and not ser (to be).

Dannia G. answered 06/20/25
Spanish teacher with 5,000+ hours of teaching experience.
Because it is an idiom. In Spanish, there are many idioms with the verb "tener", one of them is when we speak about age. An idiom means that it is an expression that does not make sense in a literal translation. So, it isn't meant to be taken in a literal sense.
Another way to look at this, the verb "tener" is use for possession, just like in English. So, if it is helpful to remember " I have X number of years of life" then you could also explain it this way or make an association like this to help you remember.
Hope this helps!
In this question, clearly we ask for the difference between "tener"="to have", and "ser"="to be" ("estar"="to be" as well, but that’s a different topic).
A way to think of this is actually hinted at by the English language itself !
When you say: "I am 12", you are not saying that your "identity" is the same thing as the number 12. You are using a short form of: "I am 12... years old"... or "My age is 12"... or "my age contains 12" or… “I have 12 degrees of old”, or "I have 12".
This expression using "old" is telling us that you are not the same thing as 12, but that something "you have/you own" (your age belongs to you) has a value/quantity of 12.
So, we see that this notion of "to have" for age is not unique to Spanish, but in English as well... we "intend" to mean it one way, but we choose to "say" it another way.
Btw, it is the same thing in French, Russian, Italian and Japanese, and many others.
Hope this helps !
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