Hello again Dennis,

Address returns a string like the following.
MsgBox Columns(1).Address

Untested but I think your code should be;

Range("b2").Value = WorksheetFunction.SumIf( _
Sheets(UserForm1_ID).Columns(1), _
Sheets("compare").Range("a2"), _
Sheets(UserForm1_ID).Columns(2))

--
Regards,

OssieMac