To delete an invoice, go to the Patient File > Invoices tab > select Invoices.

Select the Invoice, by selecting the tickbox to the left of the invoice number.

Select Delete.

The next screen will ask you to confirm by typing Delete and by giving a reason.

Select Next.

If the invoice has a payment allocated against it, select if you would like to either Make Payment Unallocated (a credit) or Delete Payment.

Or if one or more payments are associated with multiple items they can only be Unallocated.

Select Delete to confirm.

No — once an invoice is deleted, it cannot be restored directly. However, its original details aren't lost: you can find them in the Audit Log (Reports > General > Audit Log, or via the cog icon next to the patient's name) and use those details to recreate the invoice manually.

When recreating it, you can set all dates to match the original invoice — but the recreated invoice will be issued a new invoice number, since the original number can't be reused.