This is a good start, however sorry I didn't clarify before that if b1 is
#n/a, c1 will be blank and if c1 is #n/a, b1 will be blank.

How could I adapt this formula so the condition is that b1 OR c1 = #n/a,
rather than AND?

Many thanks

"Marcelo" wrote:

Hi,

selecte A1

Format | Conditional format | change to "The formula is"

=and(iserror(b1),iserror(c1))

format as you need

hth
regards from Brazil
Marcelo

"luvthavodka" escreveu:

How can I set the conditional formatting of a A1 if B1 or C1 shows #n/a?

(B1 and C1 both contain formulae that will return #n/a until the required
information is inputted elsewhere in the spreadsheet. Hence I want
conditional formatting to highlight information that is missing)