View past bills
From PhonePower Knowledge Base
You can view your past invoices by clicking on Invoices & Payments from your MyAccount menu.
Once on the Invoices and Payments page you will see the Pending Charges for your account as well as two buttons.
The first button View Invoices will display a list of previous invoice statements You can view the itemized contents of each invoice by clicking the invoice number. If you would like to print an invoice out for your records you can click the Printer Friendly link next to each invoice and a new window will open with a version of the invoice that will print out nicely.