It is not mandatory for an invoice to be signed for it to be valid , although they usually have the signature or stamp of the person issuing them. The signature gives the invoice greater probative value for the client in the event of a dispute. If we take into account that the issuer must guarantee its authenticity, it is advisable to at least put a stamp on it. Otherwise, anyone could issue invoices in our name just by putting our details on them.
It allows them to return phone number databases the product or claim for poorly provided service. It is also the instrument to exercise the right to payment. We cannot claim a non-payment if we do not have the supporting document that proves the transaction.
There are a number of legal presumptions that allow an invoice to be authenticated, such as that it is included in the accounting records of both companies and that it has been declared and the corresponding taxes have been paid.
In the case of purchases, the most common thing is to sign a document justifying receipt of the goods, so that the debt is proven, regardless of the sending and receipt of the invoice. In the case of services, the most prudent thing is to have the acceptance of a budget. Otherwise, there could be problems if the person obliged to collect rejects the operation as non-existent.