You could wrap it in an IFERROR function, and put zero in the argument for it.

=IFERROR(IF(E9=8455,VLOOKUP(Sheet1!G9,'8455'!A:B,2,0),IF(E9=8456,VLOOKUP(Sheet1!G9,'8456'!A:B,2,0),IF(E9=8457,VLOOKUP(Sheet1!G9,'8457'!A:B,2,0)))),0)

That will work in newer versions of excel. If you have an older one, you could use =IF(ISERROR(IF(E9=8455,VLOOKUP(Sheet1!G9,'8455'!A:B,2,0),IF(E9=8456,VLOOKUP(Sheet1!G9,'8456'!A:B,2,0),IF(E9=8457,VLOOKUP(Sheet1!G9,'8457'!A:B,2,0))))),0,IF(E9=8455,VLOOKUP(Sheet1!G9,'8455'!A:B,2,0),IF(E9=8456,VLOOKUP(Sheet1!G9,'8456'!A:B,2,0),IF(E9=8457,VLOOKUP(Sheet1!G9,'8457'!A:B,2,0)))))

Matt

=IFERROR(IF(E9=8455,VLOOKU

That will work in newer versions of excel. If you have an older one, you could use =IF(ISERROR(IF(E9=8455,VLO

Matt