Non-PO invoices … almost every finance team finds them troublesome. They don’t come from a formal procurement process, no one is sure who should approve, and they often slow down accounting.
With the advent of e-invoicing and Peppol, many companies expect these problems to disappear on their own. But in practice, the opposite often happens: non-PO invoices get stuck more often than PO invoices.
And that has everything to do with one crucial element: the PO number is a required field in Peppol.
In this blog, we explain why non-PO invoices cause problems in Peppol, why some invoices never arrive, and what you can do to prevent it.
What can you read on this page?
What is a non-PO invoice?
A non-PO invoice is a supplier invoice that is not linked to a Purchase Order.
Typical examples:
- Software subscriptions
- Consultancy
- Utilities (gas, water, electricity)
- Marketing costs
- Licenses
- Small purchases for which no one created a PO
For finance, this means more manual validation, more communication with colleagues and often a delay in the payment process.
Why non-PO invoices cause problems in Peppol
Although sending an invoice in Peppol usually goes smoothly, non-PO invoices regularly get stuck. This is because certain fields in Peppol are required to be completed, and missing them can result in invoice blockages or rejections.
Meaning:
1. The PO number is a required field
If an e-invoice does not contain a PO number while it is required, the invoice will be considered invalid by Peppol.
2. A good Access Point immediately blocks the invoice
The Access Point is supposed to detect that the field is missing and should reject transmission or receipt. The supplier then returns a clear error message, for example, “PurchaseOrderReference is required but missing.”
3. If the Access Point fails to do so, Peppol puts the invoice further down the chain
If the Access Point fails to do so, the invoice may be rejected further down the Peppol network. The receiving party rechecks the invoice and rejects it if mandatory data is missing. This can lead to feedback that is not always clear to suppliers, resulting in the invoice not reaching the end customer and finance having to figure out afterwards what went wrong.
Result: invoices don’t arrive at the end customer, suppliers get frustrated and finance has to figure out afterwards what went wrong.
Internal reasons that non-PO invoices are not running smoothly
Many suppliers are used to sending invoices without a PO number. They don’t fill in the field and expect the invoice to arrive as usual.
However, Peppol works more strictly than e-mail: a mandatory field that is missing means that the invoice will not be processed. And that’s exactly the point: it prevents erroneous invoices … but only if the Access Point does the validation correctly.
In practice, this often leads to problems:
- Suppliers do not know PO number is mandatory
- Organizations do not clearly communicate which field is required
- Access Points sometimes do not fully validate according to rules
- Invoices do not arrive without anyone noticing
The impact of ViDA: even stricter validation coming soon
With the advent of ViDA (VAT in the Digital Age), e-invoicing and real-time e-reporting will be even more strictly regulated in the EU. Member states must mandatorily support digital reporting by 2030, and many countries are already choosing to mandate Peppol or similar standards.
For non-PO invoices, this means that invoices with missing data, such as a PO number, will be rejected even faster. Also local validation platforms (such as Italy, Poland or France) apply additional checks on top of Peppol. In short: the need for correct invoice data and a good Access Point will only increase in the coming years.
What a good access point does for non-PO invoices
Non-PO invoices often cause delays because mandatory fields are missing. With a
A professional Access Point does this by:
✔ Strict validation on mandatory fields
An invoice without a PO number is checked by the Access Point. If necessary, corrections are applied so that the invoice still complies with the Peppol rules and is not rejected.
✔ Clear error messages
Suppliers know immediately what to adjust.
✔ Prevent invoices from “disappearing” in the chain
Anything non-compliant is rejected before shipment.
✔ Guidance and Support
Sometimes it’s unclear which fields are required or why an invoice fails. A quality Access Point guides companies so that non-PO situations don’t cause invisible roadblocks.
Processing non-PO invoices smarter: from Peppol to AP automation
Now that it is clear why non-PO invoices often get stuck and how a quality Access Point prevents this, the question arises: how to structurally improve this process?
The solution lies with AP automation. By processing non-PO invoices with a smart tool like 4CEE-invoice through Nymus, you take them out of the ad hoc process and make the payment process predictable, efficient and error-free. Finance teams get instant visibility, suppliers get paid faster, and IT can set up a streamlined, well-integrated workflow.
Practical features to process non-PO invoices
1. Automate recurring non-PO invoices
Invoices such as utilities, phone bills, rent or leases recur monthly. With 4CEE-invoice, these invoices can be automatically linked to a “spend plan” and processed completely touchlessly. This eliminates monthly manual labor and gives management insight into expenses before they occur.
2. Automate approval workflows
Non-PO invoices are automatically sent to the right person for review and approval, based on preset attributes. Thus, the correct approval person receives the invoices immediately upon receipt.
3. Automatic coding based on invoice attributes
Like PO invoices, non-PO invoices can be automatically coded based on attributes such as supplier, contact person or description. They are then automatically forwarded for payment or for confirmation to an approval person.
Summary
Processing non-PO invoices remains a challenge, especially within the strict Peppol framework. This makes the importance of a quality Access Point even more apparent: a good Access Point prevents invoices from getting stuck, provides clear error messages and guides suppliers and finance teams through the process. As a result, you lose less time with retrospective research and your billing processes run much more automatically and efficiently.
Want to discover how your organization can process non-PO invoices seamlessly and make your e-invoicing processes smarter? Contact Nymus and explore the possibilities together.
FAQ
A PO invoice is associated with a Purchase Order that has been created in advance in the purchasing process. In contrast, a non-PO invoice occurs outside of a formal procurement process, without a PO created. Non-PO invoices are often more difficult to process because approval and validation processes are less clear.
Peppol has strict validation rules for e-invoices. If a profile of the receiving organization requires a PO number to be entered, an invoice without this field will be considered invalid. The goal is to prevent erroneous invoices and standardize invoice processing.
If the Access Point validates correctly, the invoice is blocked and the supplier receives a clear error message.
If the Access Point does not validate sufficiently, the invoice may be rejected further down the chain by Peppol itself, leading to delays or the invoice not arriving at the end customer at all.
A Quality Access Point:
- Validates strictly on required fields.
- Provides clear error messages to vendors.
- Prevents invoices from “disappearing” in the chain.
- Provides guidance and support so that non-PO situations do not create invisible roadblocks.
By applying AP automation, non-PO invoices can be processed in a structured manner. This ensures:
- Better control and oversight for finance.
- Faster processing and payment of suppliers.
- Efficient workflows for IT and AP teams.
- Automate recurring invoices: for example, utilities, subscriptions and leases.
- Automate approval workflows: automatically send invoices to the right person for review.
- Automatic coding: use invoice properties such as supplier, contact or description to automatically code and forward invoices for payment or approval.
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