Courtesy is used with these nouns:
call, title

great, unfailing, utmost
common, simple (esp. AmE)
It's common courtesy to give up your seat for elderly people.

professional
She contacts clients regularly as a professional courtesy.

do sb, have, show, treat sb with
She might have done me the courtesy of replying to my letter.
You could at least have had the courtesy to let me know.

with courtesy
He listened to all the complaints with great courtesy.

courtesy to
her unfailing courtesy to everyone

a matter of courtesy
It's a matter of courtesy to write and thank people after a party.