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How to correct an incorrect invoice

An invoice is an official document issued when a transaction takes place between an exchange of goods or services for money. If after issuing an invoice you realise that you have made an error, there is a procedure you can follow to correct it. In this article, you will see how to correct an incorrect invoice.


In order to be able to change the invoice in the right way, it is important to first determine where in the invoice process it is, and which information is incorrect.

Changing invoices that have not yet been issued

If you manage to realise your invoice is incorrect before you have actually sent it to your customer, then the problem can easily be solved. You can simply edit the invoice and fix the error.

An invoice is not considered “issued” if it has not yet been delivered to the addressee.

Correcting an incorrect invoice

Changing invoices that have already been issued

If you have already issued your invoice - meaning you have sent the invoice to your customer - and only afterwards you realise that the invoice is incorrect or contains an error, you then have different options depending on what the error is.

If you would like to change the original amount issued on the invoice to either higher or lower, you will need to issue a credit note. This occurs in cases where you forgot to include a discount, or you need to issue a refund to someone for damaged goods.

Just like most other invoicing software, Debitoor allows you to create credit notes directly from the original invoice, and all details will be entered automatically.

On the other hand, if you only need to correct some details on the invoice (such as customer’s information, your information, date, or document number etc.), then you do not need to issue a credit note. Instead, you can simply create a new invoice with the corrected information, and send the new bill to your customer. It is very important however that you make sure you continue numbering your invoices with a unique invoice number, and that you do not skip numbers.

Generally speaking, you should never delete an invoice. In cases where you want to delete or amend an invoice, a credit note will usually suffice as the solution. A credit note allows you to effectively - and legally - cancel an invoice.

By law it is required that you always keep a copy of all invoices you issue, for control purposes. Authorities should always be able to see the initial invoice upon their request, even if it is incorrect.

However, many invoicing programs do allow you the option to delete the invoice, but not before warning you that it is not legally recommended.

Should you correct a proforma invoice?

The nature of a proforma invoice is to declare the seller’s commitment to provide goods or services to a buyer at a specific price, before all invoices details are known.

Since the proforma invoice is not an “official” invoice by definition, it does not hold any fiscal value. Due to this, if you find an error in a proforma invoice you have already issued, it is not necessary to issue a credit note, or to modify its content in a formal way.

Once you convert the proforma invoice to an ordinary invoice, then you can correct any incorrections you may have.