If you have only two customers (or a few only) then use IF
=IF(A2="xxx", 18, IF(A2="zzz",15,""))

If you have a lot of customers then use VLOOKUP
=VLOOKUP(A2,E:F,2,False)
after entering Customer and Value combinations in Col E & F

"George" wrote:

In Excell 2007, I would like to put the names of customers in one cell and
when I chnage the customer I would like the amount in another cell to change.
i.e. If cell A2 has xxx customer, I would like cell B2 to equal 18. When I
change cell A2 to zzz customer, I would like cell B2 to equal 15. Which
formula should I use for this and can you help me with the formula?