glad you could drop by

(I'm) glad you could drop by.

 and (We're) glad you could drop by.; (I'm) glad you could stop by.; (We're) glad you could stop by.
a phrase said by the host or hostess (or both) to a guest who has appeared suddenly or has come for only a short visit. Tom: Good—bye. Had a nice time. Mary: Thank you for coming, Tom. Glad you could drop by. Tom: Thank you so much for having me. Sally: We're glad you could drop by.
See also: could, drop, glad