HP Store will invoice your order the following day after your order ships.
When you place your order you will have the option to choose how you would like to receive your invoice (electronic or paper).
Electronic format (PDF):
By default HP Store will email you your order invoice in a PDF format on the following day that your order ships from our warehouse
If you wish to receive the invoice in a paper format you can request this during the checkout process by selecting Hard copy on the Order review screen.
If you do not have Adobe Reader,download here.