Is e-invoicing via email a viable way forward?

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foto Jaap Jan Nienhuis

Jaap Jan Nienhuis, Financial Services Consultant at Innopay

The answer is yes and no.
Yes, as email is a way for small businesses to exchange e-invoices between each other.
No, as large corporates often have requirements regarding authenticity, integrity, reliability and deliverability that are insufficiently addressed by email. And they require a better secure transfer protocol.

That is why Simplerinvoicing offers usability in both email with Simplerinvoicing LITE and in a more secure environment with Simplerinvoicing FULL.

Simplerinvoicing FULL is based on the OpenPEPPOL standards for transporting invoices from sender to receiver. Simplerinvoicing FULL is a standardized transport protocol that enables a sending system (for example ERP software) to send an e-invoice to a receiving system (for example an e-invoicing service provider).

Why not just use email as a transport channel instead and put a UBL file as an attachment in the email?
For a part of the market this indeed is a viable solution. In the SME segment email is already widely adopted to exchange PDF invoices. In this segment adding a UBL to the email greatly enhances the value for the receiver, as he does not have to process a PDF manually by typing it in an ERP system or running an OCR service over the PDF file.

The benefits of email as transport channel are:

  • Email is universally available.
  • Email is widely adopted, and (almost) everybody has an email address, hence is addressable.
  • The email protocol (SMTP) has the flexibility to send messages with attachments, including XML attachments.

However, there are many corporates that deal with large volumes of invoices and that have requirements that cannot easily be addressed using email. These requirements are:

  • Reliability and deliverability guarantees that an e-invoice is delivered to an end-user (e.g. the email does not get stuck in spam filters), and delivery cannot be denied (in technical terms: non-repudiation).
  • Security, ensuring that an invoice is not changed during transport.
  • Authenticity, ensuring that the sender of an email is who he claims to be.
  • A transparent framework arranging the liabilities of the parties vis-a-vis each other if fraud is committed with invoices.

For some of the above issues email has solutions, including the use of certificates, secure transport, but this requires additional capabilities on top of the email network, which breaks the advantage of the universal reach that email has.

So, for companies that want to send e-invoices to both corporates and their SME counterparties, Simplerinvoicing Service Providers offers Simplerinvoicing FULL: a secure environment that uses a standardized transport protocol.

Companies that do not need this level of integration with large corporates and are comfortable using email, can use Simplerinvoicing LITE: the same UBL invoice but transported via email.

More information
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