GUIDE · FOR BUSINESSES
For years an “invoice” could be a PDF attached to an email. Across Europe that is changing: governments now want invoices as structured data that software can read and send to the tax authority. If you run a small business, here is what is changing, when, and what your billing software needs to do about it.
Under the new rules, an e-invoice is a file in an agreed structured format — usually XML — that the buyer’s software can read automatically, without anyone typing the numbers in again. A PDF, a scan or a photo of a paper invoice does not count, even if it is sent by email.
Governments are doing this to close VAT gaps and to see transactions closer to real time. For businesses, the upside is fewer typing mistakes, faster payment and less paperwork. The downside is that old billing tools which only produce PDFs will stop being enough.
Rules differ by country and change often, so always confirm with your accountant or the official tax website. As of October 2026, the main dates for business-to-business (B2B) invoices are:
You will see a lot of names. Most of them are versions of the same European standard (EN 16931), adapted for one country or network.
Use this as a checklist when you review your current tool or choose a new one:
We build Karobar, a billing and stock app used by shops in Pakistan. The tax rules there are different, but the hard parts of invoicing are the same everywhere, and they are worth checking in any system you use.
Returns are their own document. In Karobar, a sale return is recorded against the original bill and puts the stock back — the original bill is never quietly edited. That is exactly how credit notes work under e-invoicing rules.
A bill must never be created twice. Karobar can save bills offline and sync them later, and each one is applied exactly once, even if the network drops or someone taps “save” twice. Duplicate invoices are a real compliance problem once every invoice is reported to a tax authority.
Data must survive a bad day. Karobar runs nightly backups, and sale and purchase bills can be shared as a PDF or by email. Under e-invoicing, the structured data becomes the legal record, so backups and exports matter more, not less.
If you use a mainstream accounting package, check whether your provider already supports your country’s format — many do, sometimes as a paid add-on. That is usually the cheapest path.
If your invoices come out of your own system — a booking tool, an order system or an industry-specific app — you do not need to replace it. A developer can add an e-invoicing step that sends each invoice to a certified Peppol access point or approved platform through its API, and brings incoming supplier invoices back in.
Custom work makes most sense when invoicing is tied closely to how you operate: invoices created from jobs, orders or bookings, stock that has to move with each invoice, or several companies or currencies in one system.
E-invoicing is coming to most of Europe in the next few years, and small businesses are usually last in the timeline, which gives you time to prepare calmly. Start by asking what your current tools can do. If invoices sit inside a system you built or need to build, TECHROOF.IT can help you connect it properly. This guide is general information, not tax or legal advice.