Invoice template in PDF: structure and required lines
One clarification first: this page is about the invoice as a PDF document, not about statutory electronic invoicing. Where your country mandates e-invoicing, the machine-readable file comes from your accounting software. The PDF remains useful as the human-readable copy your customer actually reads.
What it must contain
- An invoice number and date, in a gap-free sequence.
- Full issuer details: legal name, address, VAT or tax number.
- Full customer details, including their tax identifiers.
- Line items: description of the goods or service, quantity, unit price, discount, tax rate.
- A tax summary: net and tax per rate applied.
- The document total and, if different, the amount payable.
- Payment method and due date, with bank details.
- Any references the customer requires: purchase order, delivery note, project code.
Mistakes we see most often
- Gaps or duplicates in the numbering — typical when invoices live in per-customer folders.
- A single total with no split between net and tax.
- Confusing the document date with the tax point or the due date.
- Omitting the reference the customer's system needs, so the invoice bounces back.
- Descriptions that do not let the customer work out what they are paying for.
Typical structure
| Header | Issuer with logo and tax details |
| Recipient | Customer with full tax details |
| References | Invoice no. 2026/112 — 11 Sep 2026 — PO-88 |
| Lines | Description · Qty · Price · Discount · Tax rate |
| Tax summary | Net and tax per rate |
| Totals | Document total · Amount payable |
| Payment | IBAN · due date · method |
Frequently asked questions
Is a Workio PDF a valid electronic invoice?
No, and it does not claim to be. Workio produces a PDF. Where a country mandates a structured e-invoice, that file comes from your accounting software; Workio complements it rather than replacing it.
What is a PDF invoice good for, then?
As the readable copy the customer receives, for the many markets where PDF is still the norm, and to keep track of what you have invoiced and collected without opening your accounting system.
How do I turn an accepted quote into an invoice?
Convert the document in Workio: the accepted quote becomes a proforma or an invoice keeping the lines, discounts and customer, and retaining a reference back to the original.
Can I run several companies with different tax numbers?
Yes, with multi-brand in Workio Pro: each company has its own logo, tax details and numbering, and the documents stay separate.