Option Explicit
Sub concatenate()
Dim a, i As Long, j As Long, n As Long
Application.ScreenUpdating = False
With Range("A1").CurrentRegion
'With Range("A1").CurrentRegion.Resize(, 2)
a = .Value
With CreateObject("Scripting.Dictionary")
.CompareMOde = 1
For i = 1 To UBound(a, 1)
If Not .exists(a(i, 1)) Then
n = n + 1: .Item(a(i, 1)) = n
For j = 1 To 2
a(n, j) = a(i, j)
Next
Else
a(.Item(a(i, 1)), 2) = a(.Item(a(i, 1)), 2) & ", " & a(i, 2)
End If
Next
End With
With .Offset(, .Columns.Count + 2)
.CurrentRegion.Clear
.Resize(n).Value = a
With .CurrentRegion
.Font.Name = "calibri"
.VerticalAlignment = xlCenter
.Borders(xlInsideVertical).Weight = xlThin
.BorderAround Weight:=xlThin
.Columns(2).HorizontalAlignment = xlLeft
With .Rows(1)
.Font.Bold = True
.Interior.ColorIndex = 45
.BorderAround Weight:=xlThin
End With
End With
.Columns.AutoFit
End With
End With
Application.ScreenUpdating = True
End Sub