Hi,
Try this:

Dim lRow As Long

Const Formula As String = "=sum(b1:bX)"

lRow = Cells(Rows.Count, "B").End(xlUp).Row ' find last row in colum b

Cells(lRow + 1, "B") = Application.Substitute(Formula, "X", lRow) '
substitute X by lrow in SUM formula


HTH
"Diane" wrote:

I am writing some code to clean up data I imported into excel. I will have a
vraiable number of rows each time I run the macro.

Always in Coulmn B is the number I want to sum. What function can I use to
count the number of rows I have & then put the sum of Column B in the next
free row. i.e.

Rows 1-5 have data , put sum of B1:B5 into B6 where next time it could be
B1:B10 sum in B11.

Thank you.
Regard,
Diane