Hi Ricki,

Put this formula in C1 and fill down. The cells will be blank or have a
number in them. These are duplicates.

=IF(COUNTIF($A$1:$A$5,B1)0,B1,"")

HTH
Regards,
Howard

"Ricki Miles" wrote in message
...
I am working in Excel 2003. I have two columns of numbers (ID numbers for
employees of 6 digits each). If a number appears in column A (there are
no
duplicates of this number in column A), the number must NOT appear in
column
B. Is there any way, besides VBA, to check if a number appearing in
column
A is also listed in Column B?

Thanks,

Ricki