Try

=IF(ISNA(LOOKUP(B5,Lookup!$A$1:$A$100,Lookup!$B$1: $B$100,0),"No
Match",LOOKUP(B5,Lookup!$A$1:$A$100,Lookup!$B$1:$B $100,0))

Notice the extra 0 as the last argument in the Lookup function. This
requires and exact match. If there is no match, the function returns a #NA
error


"Steve Elliott" wrote:

How do I get a formula that does a standard LOOKUP, but returns an exact
match, rather than matching the nearest figure in the lookup table.

EXAMPLE:
I have a formula thus: =LOOKUP(B5,Lookup!$A$1:$A$100,Lookup!$B$1:$B$100)

However, if cell B5 contains say 1562 and the closest match in the lookup
table is 1540, then it returns the result in column B for 1540. I would
like it to return the words "No Match" if it can't find an exact match.

Any ideas?

Thanks. Steve.