One way:

=IF(OR(ISBLANK(K10),ISBLANK(L10)),"",L10-K10)

alternatively:

=IF(COUNT(K10:L10)<2,"",L10-K10)




In article ,
"Ian Elliott" wrote:

I have a cell formula:
=IF(OR(ISBLANK(K10),ISBLANK(L10)),,L10-K10)
Which makes the cell zero if either of k10 or l10 is blank, (and subtracts
the two if not), but I want to make the cell blank rather than zero.