appropriate way of asking between 'can' and 'could'

Hi

I want to know what the most appropriate way of asking between ‘can‘ and ‘could’

Is it Can I speak to Mr … ?

Or Could I speak to Mr ….?

Hi,

In that context ‘could’ is a little more formal/polite.

Alan

I think it often depends on the social relationship between you and the listener. If it is fairly familiar, you can use “can”.