try in C1
=if(countif(B:B,A1)0,"Y","")
and copy down



"shauny" wrote:

Hi

I have 3 columns, A, B and C. A and B contain email addresses, and I
want to set C to "Y" if the email address in A is also in B.

A has thousands of entries, B has hundreds, so its not a simple matter
of sorting them and manually setting C. Where the email addresses
match, they will match exactly (they're from the same source table).

Spreadsheet formulae are not my forte, and the help on lookup hasn't
really helped.

Any ideas?


Shaun