Do you mean something like

=IF(ISNUMBER(MATCH(A2,July!A2:A100,0)),VLOOKUP(A2, July!A2:H100,5,False),100)

where A2 is the customer number and the invoice number is in column E on the
July sheet

--

HTH

RP
(remove nothere from the email address if mailing direct)


"lil'bibbib" wrote in message
...
Hello... I am currently building database for my July and August
customers.
Because I am doing a promotion, those that purchased in July will be able
to
get a free course in August. I would like to know how do I build it so
that
in the "Amount" column, it would search July data and if the customer
number
corresponds then it will return the invoice number in July (which is set
up
next to the "Amount" column) and if cant find the customer number, then it
should display "100".