On 5 Jun, 17:18, "Earl Kiosterud" wrote:
Shaun,

This formula will tell you how many matching entries for A2 exist anywhere in column B:
COUNTIF(B:B,A2)

This will put "y" in the cell
=IF(COUNTIF(B:B,A2),"y","")

Since there are more entries in column A than in B, I don't know where you want to put the
formula. Should it match B against A (the opposite of above)? If so.

=IF(COUNTIF(A:A,B2),"y","")

--
Earl Kiosterudwww.smokeylake.com

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-----------------------------------------------------------------------"shauny" wrote in message

oups.com...

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

Hi

Excellent - many thanks people!

Regards
Shaun