Bonjour quentinmgt, le forum,
Un essai....
Sub test()
Dim dl As Long
dl = Sheets("Feuil1").Range("A" & Rows.Count).End(xlUp).Row
Range("C11").FormulaR1C1 = _
"=IF(R[0]C[-2]="""","""",IF(R10C2="""","""",INDEX(BASEINVENTAIRE,R[0]C[-2],3)))"
Range("C11:C" & dl).FillDown
End Subb
Cordialement,