When processing a supplier invoice there are two boxes for the date field. The booking date and the invoice date.
The booking date refers to the financial period you need the invoice to be posted into.
The invoice date is the date of the invoice you are processing. These two dates can be different and will impact on your accounts in this way:
Booking date - this is the period the invoice will be booked/posted to your financial reports, profit & Loss etc and your VAT Return. When you select to process a new supplier invoice the system will always give you todays date. If you need the invoice to be booked/posted in a period other than the current one you are working in you can change the date appropriately.
Invoice date - this relates to the date on the invoice you are processing. If you have an invoice that is dated in the prior month/accounting period you are currently working and enter the date of the invoice here and enter the booking date as the current month the invoice will be posted in your current month but appear on your aged creditors report with the invoice date you have entered.
This allows you to recognise older invoices on your aged creditor report.