fromEnglish Grammar Today
The countable nounpermit(pronounced/ˈpɜ:mɪt/) refers to an official document that allows you to do something or go somewhere. The uncountable nounpermissionrefers to when someone is allowed to do something.It does not refer to a document:
You need to have a workpermitbefore you can work.
Not:You need to have a work permission…
I have a parkingpermitwhich allows me to park on the street outside my house.
Not:I have a parking permission…
We use the wordpermissionwith an infinitive withto:
Could I have yourpermissionto leave work early on Friday?
We applied forpermissionto build a house here but our application was refused.