To Archive an Invoice in the Management Portal,
 

  1. Select CRM from the top menu bar.
  2.  From the drop-down select Invoices. 
  3.  Check the box next to the Invoice you are wanting to Archive.
  4. At the bottom of the page select the Select Action drop-down.
  5. Choose Archive from the drop-down. 
  6. Press Go to Archive the Invoice.