Lister une plage de cellules pour pouvoir les comparer

For j = 1 To Ws1.Cells(Rows.Count, 1).End(xlUp)(2).Row

For j = 1 To Ws1.Cells(Rows.Count, 1).End(xlUp).Row

Option Explicit
Sub Macro1()
Dim i&, j&, Ws1 As Worksheet, Ws2 As Worksheet
Sheets("Fusion").Cells.ClearContents
Sheets("Salaires actuels").Cells.Copy Sheets("Fusion").Range("A1")
Set Ws1 = Worksheets("Fusion"): Set Ws2 = Worksheets("Salaires au 31 12")
     With Ws2
         For i = 1 To .Cells(Rows.Count, 1).End(xlUp).Row
             For j = 1 To Ws1.Cells(Rows.Count, 1).End(xlUp).Row
                If (Ws1.Cells(j, 2) & Ws1.Cells(j, 3) & Ws1.Cells(j, 4)) = (.Cells(i, 2) & .Cells(i, 3) & .Cells(i, 4)) Then
                    Ws1.Cells(j, 18) = .Cells(i, 13)
                    Ws1.Cells(j, 19) = .Cells(i, 14)
                    Ws1.Cells(j, 20) = .Cells(i, 17)
                 Else
                     Ws1.Cells(j, 1) = .Cells(i, 1)
                     Ws1.Cells(j, 2) = .Cells(i, 2)
                     Ws1.Cells(j, 3) = .Cells(i, 3)
                     Ws1.Cells(j, 4) = .Cells(i, 4)
                     Ws1.Cells(j, 5) = .Cells(i, 5)
                     Ws1.Cells(j, 6) = .Cells(i, 6)
                     Ws1.Cells(j, 7) = .Cells(i, 7)
                     Ws1.Cells(j, 8) = .Cells(i, 8)
                     Ws1.Cells(j, 9) = .Cells(i, 9)
                     Ws1.Cells(j, 10) = .Cells(i, 10)
                     Ws1.Cells(j, 11) = .Cells(i, 11)
                     Ws1.Cells(j, 12) = .Cells(i, 12)
                     Ws1.Cells(j, 15) = .Cells(i, 15)
                     Ws1.Cells(j, 16) = .Cells(i, 16)
                     Ws1.Cells(j, 18) = .Cells(i, 13)
                     Ws1.Cells(j, 19) = .Cells(i, 14)
                     Ws1.Cells(j, 20) = .Cells(i, 17)
                 End If
             Next j
         Next i
     End With
End Sub

Option Explicit
Sub CA()
  Dim W As Worksheet, C As Range, R As Range
  Set W = Sheets("Fusion")
  W.Cells.Clear
  Sheets("Salaires au 31 12").Cells.Copy W.[A1]
  With Sheets("Salaires actuels")
    For Each C In .Range("A2", .Cells(Rows.Count, 1).End(xlUp))
      Set R = W.[A:A].Find(C)
      If Not R Is Nothing Then
        If C(1, 2) = R(1, 2) And C(1, 3) = R(1, 3) Then
          C(1, 13).Resize(1, 2).Copy R(1, 18)
          C(1, 17).Copy R(1, 20)
        End If
      Else
        C.Resize(2, 20).Copy W.Cells(W.Cells(Rows.Count, 1).End(xlUp).Row + 1, 1)
      End If
    Next
  End With
End Sub