A function called from a worksheet cell can only return a value (to that
cell) neither it, nor any macros called by it can alter the Excel
environment in any way (change format, change values in other cells, etc).

Assuming that you want to execute a "macro" for one of these forbidden
purposes, you would have to the Worksheet_Change event.

Jerry

Rich wrote:

hello.

is it possible to input a function into excel where if a cell does/doesnt
meet a certain critera then excel automatically executes a macro?

e.g. if A20 equals 22-12-05 then excel will run macro Date1.

thank you for any assistance and merry christmas!