reason of/for

[MadHorse]

I have not yet tell you the reason _ my visit.
Of or for?
Thanks.

[Fizi]

I have not yet tell you the reason _ my visit.
Of or for?

I have not yet told you the reason for my visit.

But if you use 'purpose' in your sentence, you would use 'of'.

I have not yet told you the purpose of my visit.