Please try this, it should work for you,

```
Sub AddCommas()
Dim s As String
Dim i As Long
Dim j As Long
For k = 1 To 20
For i = 1 To Rows.Count
s = ""
If Not IsEmpty(Cells(i, k).Value) And Int(Len(Cells(i, k)) / 10) >= 1 Then
For j = 1 To Int(Len(Cells(i, k).Value) / 10) + 1
If j = 1 Then
s = s & Left(Cells(i, k).Value, j * 10) & ","
Else
If j = (Int(Len(Cells(i, k).Value) / 10) + 1) Or (Len(Cells(i, k).Value) / 10) = j Then
s = s & Mid(Cells(i, k).Value, ((j - 1) * 10) + 1, 10)
Else
s = s & Mid(Cells(i, k).Value, ((j - 1) * 10) + 1, 10) & ","
End If
End If
Next j
Cells(i, k).Value = s
End If
Next i
Next k
End Sub
```

Adjust the `k`

variable and `i`

variable as per your starting row position and number of columns. Hope this helps.

15

solved Prepare Macros which add comma after every 10 digit in a column [closed]