Try this...

Select the range of cells. Assume this range is B2:B201
Goto the menu FormatConditional Formatting
Select the Formula Is option
Enter this formula in the box on the right:
=MATCH(B2,K$2:K$8366,0)
Click the Format button
Select the desired style(s)
OK out

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Biff
Microsoft Excel MVP


"HANK" wrote in message
...
I have two columns of numbers. One small set (25-200, imported daily) of
numbers in column B, and 8365 unique numbers in column K. I would like to
use conditional formatting to tell me if any of the numbers imported into
column B match any of the 8365 unique numbers in column K. If so, I would
like the numbers in column B that match to turn Red.