The term electronic invoice (e-invoice) is often confused with a PDF sent by email. That’s a misunderstanding that will start costing companies time and money as mandates roll out. A true e-invoice is a structured data document, not an image. This article explains what it looks like, its mandatory fields, and why it is fundamentally better than paper and PDF.
A PDF is not an e-invoice
A PDF invoice is essentially a scanned or printed image of text. A human reads it fine, but a computer cannot — the buyer’s accounting system has to retype it manually or run error-prone OCR. That’s why a PDF emailed as an attachment does not meet the structured e-invoicing requirements introduced by the 2027 mandate and ViDA.
Structured e-invoices: UBL and the EN 16931 norm
A real e-invoice is a file in UBL (Universal Business Language) — a machine-readable document where every value has a precisely defined place. The European norm EN 16931 defines which fields an invoice must contain and in what form; Peppol BIS Billing 3.0 is the profile these invoices travel in across the Peppol network.
The benefit: when an invoice conforms to the norm, any system on the other side reads it without errors — whether the buyer runs SAP, a local accounting package or a custom ERP.
Mandatory fields of an e-invoice
An e-invoice contains the same details as a classic invoice, just in a precise structure:
- identification of supplier and buyer, including company and VAT IDs,
- dates of issue, supply and payment,
- individual line items with quantity and unit price,
- VAT rates and amounts by tax treatment,
- payment method and details (IBAN, reference),
- reference data (order number, contract, etc.).
A good Access Point validates every invoice against EN 16931 before sending, so formal errors — a missing VAT ID, a wrong rate — are caught up front rather than surfacing as a buyer dispute.
Why an e-invoice beats paper and PDF
- No retyping or OCR — data flows straight into accounting.
- Fewer errors and disputes — mandatory fields are verified.
- Faster payment — the invoice is in the buyer’s system in seconds.
- Lower cost — no paper, postage or manual processing.
- Audit trail — delivery is confirmed and traceable.
How to start sending and receiving e-invoices
You don’t need to change your accounting software or set up an IT department. Either you use the Peppol Box web inbox, or we connect your accounting/ERP system via REST API and invoices flow automatically. Receiving e-invoices is free forever with Verteco, with sending on a clear flat fee — details in the pricing.
Get ready ahead of time — activate your free inbox today.
