One way is with 2 helper columns.

Assuming your lists are in A1-A100 & B1-B100

put this array formula (ctrl+shift+enter) in C1
=IF(COUNTIF($A$1:$A$100,B1)=0,B1,"")
and drag down as required

put this array formula (ctrl+shift+enter) in D1
=IF(COUNTIF($B$1:$B$100,A1)=0,A1,"")
drag down as required.

The 2 list produced are unique items

Mike








" wrote:

Hello, I'm not the most savvy excel user, so this could be a simple
question. My problem is this: I have two listsof data, a master list
and a subordinate list. What I would like to do is compare the two
lists and have excel subtract out any overlapping data, outputting a
third list of completely unique values. Any help would be so much
appreciated.

Peter