Hi
do you really mean 'worksheet' and not 'workbook'. For the latter one
you may have a look at the following repost. It assumes you have a
invoice template (*.xlt file)

----------------
one way (using the Windows registry for storing the last number). Put
the following code in the workbook module (not in a standard module) of
your template:
- It changes cell A1 of the first sheet
- you may change the key identifiert according to your needs (e.g.
DEFAULTSTART, MYLOCATION, etc.)

Private Sub Workbook_Open()
Const DEFAULTSTART As Integer = 1
Const MYAPPLICATION As String = "Excel"
Const MYSECTION As String = "myInvoice"
Const MYKEY As String = "myInvoiceKey"
Const MYLOCATION As String = "A1"
Dim regValue As Long

With ThisWorkbook.Sheets(1).Range(MYLOCATION)
If .Text < "" Then Exit Sub
regValue = GetSetting(MYAPPLICATION, MYSECTION, _
MYKEY, DEFAULTSTART)
.Value = CStr(regValue)
SaveSetting MYAPPLICATION, MYSECTION, MYKEY, regValue + 1
End With
End Sub

--
Regards
Frank Kabel
Frankfurt, Germany

"unkown" schrieb im Newsbeitrag
news:niscc.35943$Ig.27302@pd7tw2no...
I need a auto invoice numbering on a new worksheet that can add a
consequence invoice number from the previous worksheet number.

Any help is greatly appreciated.