Can i add old sale invoices that have already been calculated in a previous vat period by bank deposits, so I don't want them calculating again for my next vat return ?

Hi debbie35,

You would need to enter the transactions with No VAT as any transactions with a VAT code associated will automatically show on the open return if you already have a filing recorded in QuickBooks.

If you have not yet created any filings on QuickBooks, you can changed the date of the open return period and enter the transactions with the applicable VAT codes to mark the periods with the transactions as filed until you get to your current open period.

Let us know if you have any further questions on this!