Salut Ventura,
Re, sabV , au taquet, dis-donc!
autre façon de faire en s'appuyant sur l'événement Worksheet_Change()
Private Sub Worksheet_Change(ByVal Target As Range)
'
Application.EnableEvents = False
'
If Not Intersect(Target, Union(Range("L:L"), Range("P:P"))) Is Nothing Then
Range("P" & Target.Row).Value = IIf(Range("P" & Target.Row).Value = "" And Range("L" & Target.Row).Value <> "", _
Range("L" & Target.Row).Value, Range("P" & Target.Row).Value)
End If
'
Application.EnableEvents = True
'
End Sub
A+