C1: =IF(COUNTIF($B:$B,B1)1,"a","")

format as Marlett font, and copy down

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HTH

Bob Phillips

"j-p-c" <. wrote in message ...
column A has peoples names and B has their phone numbers.
if both b1 and b18 have the phone number 123456 I would like the C column
(c1 and c18) to have a tick or something to show that those lines have the
same number. or to make both the phone numbers highlight?

how can I do this.

I have tried but have no idea where to start.


thanks