Italian Phrase of the Week: Sì, lo so. (Yes, I know.)

A very simple yet incredibly useful phrase in Italian is Sì, (io) lo so which means Yes, I know or Yes, I know that in English. It is made up of the following components:

( Yes ) + io ( I ) + lo ( direct object pronoun ‘it’ ) + so (first person conjugation of sapere ‘to know’)

Important: The reason I’ve placed io – the word for I in Italian – in brackets is because Italians normally omit personal pronouns unless it becomes absolutely necessary to identify the subject.

When I know is followed by a noun, verb or clause in English, you can use so on its own in Italian. For example:

So che Giulia non viene oggi.

I know Giulia isn’t coming today.


So dov’è la macchina.

I know where the car is.


The set expression I know however (either on its own or followed by the pronoun that) is always rendered in Italian with lo so (literally: I know it) and never simply with so. You can decide to add the (yes) or skip it, just as in English.

Giulia non viene oggi. – (Sì,) lo so.

Giulia isn’t coming today. – (Yes,) I know (that).


kids raising hand in front of their teacher in class
Maestro, lo so! – Teacher, I know!

The same rule applies to the negative sentence I don’t know (non lo so) in Italian.

Dov’è la macchina? – Non lo so.

Where is the car? – I don’t know.


The only parts of speech you will regularly see accompanying lo so are adverbs such as the ones below:

  • Lo so già = I already know
  • Lo so bene = I know well
  • Lo so benissimo = I know very well
  • Lo so più che bene = I know more than well
  • Lo so fin troppo bene = I know only too well

Knowing how to say I know in Italian is, of course, extremely useful but being able to talk about other people is just as important. In the chart below, you can see all the different personal pronouns paired with the verb sapere (to know).

(Io) lo so.
I know.

(Tu) lo sai.
You know. (informal)

(Lui) lo sa.
He knows.

(Lei) lo sa.
She knows.

(Noi) lo sappiamo.
We know.

(Voi) lo sapete.
You know. (plural)

(Loro) lo sanno.
They know.

(Lei) lo sa.
You know. (formal)

Leave a Comment