Assume you data is in A1 going down column A.

in B1 put in a formula

=if(Countif($A$1:A1,A1)=1,"Keep","Delete")

then drag fill this down the column.

select A1 and then do Data=Filter=Autofilter

In the dropdown in B1, select Delete.

Then highlight all the rows below Row A and do Edit=Delete.

Now do Data=Filter=Autofilter to turn off the autofilter.

Only the unique list should remain.

If this isn't what you want, post back with what you mean by UDF. Generally
a UDF refers to a vba custom function that is used in a worksheet as a
formula - but formulas can't change existing cells - they can't delete data
inplace.


--
Regards,
Tom Ogilvy


"Mike" wrote in message
...
Can anyone help me with a UDF to remove early duplicates
from a list?

Example:
Input:
A
B
A
C
B

Output:
A
C
B

Thanks,
Mike