E-invoicing in Belgium: the complete guide for SMEs

Updated 26 May 2026, by the by Watson editorial team.

Since 1 January 2026, electronic invoicing has been mandatory for Belgian VAT-registered businesses on B2B transactions. A PDF, Word document or paper invoice no longer counts. Your invoice has to be sent and received as a structured electronic invoice through Peppol, the pan-European e-invoicing network adopted by Belgium for this mandate. FPS Finance (the Belgian Federal Public Service for Finance) allowed a tolerance period during the first quarter of 2026, but that has now ended.

Anyone who is not yet ready risks penalties of the same kind as for other VAT breaches. The switch takes some organisation, but it also brings clear benefits: less manual work, fewer errors and faster processing. In this guide you will read what you need to know as an SME (small or medium-sized enterprise), without jargon.

At a glance

Since 1 January 2026, electronic invoicing via Peppol has been mandatory for all VAT-registered businesses in Belgium, for B2B transactions.
PDF, Word and paper are no longer accepted between businesses.
FPS Finance allowed a tolerance period during the first quarter of 2026, but that has now ended. Anyone who is not yet ready risks penalties of the same kind as for other VAT breaches.
Those who have already switched often notice the difference quickly: less typing, fewer errors and smoother payment follow-up.
Two tax support measures lower the threshold: an enhanced cost deduction of 120% on invoicing software and a digital investment deduction of 20%.

What exactly is e-invoicing?

E-invoicing is not the same as ‘sending an invoice digitally’. A PDF is digital, but it is not a true e-invoice. The difference lies in the structure. An e-invoice is a structured XML file that can be read directly by accounting software. At both ends: by the sender and by the recipient.

Such a file contains fixed fields: supplier, customer, date, VAT number, items, amounts and VAT amounts. The software reads that data automatically. No one has to retype amounts or process invoices manually.

Compare it to an address on an envelope. A person can read it. But a barcode can be scanned, sorted and processed automatically. That is exactly what e-invoicing does for your bookkeeping.

Who falls under the obligation?

The obligation applies to all VAT-registered businesses in Belgium, for their B2B transactions (business to business).

Required

Every business with a Belgian VAT number.
Invoices to Belgian customers with a VAT number.
Freelancers and self-employed persons, as soon as they are VAT-registered.

Not required (for now)

B2C transactions, meaning sales to private individuals. A restaurant, a hairdresser or a retailer selling to consumers still falls outside the scope.
Invoices to foreign customers. There, the rules of the country in question apply.
Anyone covered by the small business scheme who does not charge VAT.

Grey area

B2B transactions with foreign businesses that are not on Peppol. Transitional arrangements apply here. How to handle this in practice, you can read in “What if your client is not on Peppol?”.

What happens if you do not get it sorted in time?

FPS Finance operated a tolerance period for the first quarter of 2026. During that period, inspectors did not impose penalties for breaches specific to the new obligation, provided you could show that you were preparing your transition on time and in a reasonable manner.

That tolerance period ended at the end of March 2026.

From April 2026 the standard VAT rules apply again in full. Depending on the nature of the breach, substantial fines may follow, in line with the general VAT penalties. For an SME sending dozens of invoices a month, that is not an administrative detail.

What are the benefits?

The benefits are confirmed by everyone who has already made the switch. We list them in order of visibility in the short term.

Lower cost per invoice

E-invoicing reduces the cost per invoice. You save on printing, postage, processing, follow-up and error correction.

VLAIO (the Flemish agency for innovation and entrepreneurship) and software vendors point to savings that can run to several euros per invoice. For an SME with many incoming and outgoing invoices, that adds up quickly over a year.

Faster processing and payment

Electronic invoices are processed automatically. Accounting firms and SMEs report noticeably shorter payment terms in practice, which benefits your cash flow.

Fewer errors

No retyped amounts.
No scanning misunderstandings.
No incorrect VAT amounts caused by reading errors.

The software reads exactly what the sender wrote. Full stop.

Greater security

Peppol is a closed network with accredited access points. Your invoice does not just turn up as a loose attachment from an unknown email address.

That makes certain forms of invoice fraud harder. Think of fake suppliers, altered account numbers or counterfeit invoices that mimic real ones.

Tax benefit when you switch

Two support measures lower the entry threshold:

An enhanced cost deduction of 120% on invoicing software subscriptions, for income years 2024 through 2027.
A digital investment deduction of 20% for digital investments from 1 January 2025.

Anyone who combines both often pays off their software investment within a single accounting year.

How does it work technically?

In four steps:

Step 1. Connect to a Peppol access point. Your accounting software or e-invoicing platform does this for you. Most modern packages have the Peppol connection built in as standard.

Step 2. Draw up the invoice in your software. That works as before. You click ‘send’.

Step 3. The invoice leaves as a structured XML file over Peppol. The network routes the document to your customer’s access point.

Step 4. Your customer receives the invoice automatically in their accounting software. It appears straight away as an incoming invoice, ready for processing.

You do not need to know which package your customer uses. Peppol forms the standardised layer between all those software systems.

Which software suits your SME?

There are several good solutions on the Belgian market, including Odoo, Exact, Octopus, Yuki, Teamleader, Horus, Silverfin, Billit and Winbooks. Which software suits you depends on your activity, your volume and your current bookkeeping process.

For small self-employed people without staff, simple packages are often enough.

For SMEs with employees, multiple users or more complex processes, you usually need a more robust package.

For medium-sized companies or businesses with several entities, integration with existing systems matters more.

For accounting firms, office licences, workflows and file management play a larger role.

Important: do not choose on price or interface alone. Also choose based on the fit with your accountant.

What if you are not yet ready?

There are three typical scenarios.

Scenario A: you still work with Excel or Word

Then you have to switch. Excel and Word no longer suffice for B2B invoicing.

Choose an e-invoicing package that suits your volume and your way of working. For sole traders, low-threshold solutions exist. The net cost usually stays limited, certainly if you make proper use of the tax support.

Scenario B: you have accounting software, but do not know whether Peppol is active

Contact your vendor or your accountant.

Activating Peppol is often not a full installation, but a setting or registration within your existing package.

Scenario C: you have Peppol, but do not know whether it works

Send a test invoice to your accountant or to a client who is already on Peppol.

Does the invoice arrive correctly? Then you are fine.

Does it not arrive? Then there is likely a configuration or routing issue. Best to sort that out at once, before real invoices start getting stuck.

What does it cost?

The cost usually consists of three parts.

Software subscription. Depending on package and scale, between €8 and €150 per month for most SMEs. After the 120% deduction and the investment deduction, the effective net cost often sits between €6 and €80 per month.

One-off implementation. If you switch from an existing package, count on a few hours of support from your accountant or software vendor.

Training. Most modern packages are fairly intuitive. For many managing directors, a short briefing or a session of one to two hours is enough.

The real gain does not sit in the software itself, but in the new routine: creating correctly, sending correctly, following up correctly.

What does by Watson do for you?

by Watson supports SMEs and self-employed people with:

The choice of an e-invoicing package that fits your current bookkeeping.
The installation and the Peppol connection.
First-month follow-up: checking that invoices leave and arrive correctly.
Improving your tax position by applying the 120% deduction and the investment deduction correctly.
Handling special situations (foreign customers, B2C activities, transitional arrangements).

Is your bookkeeping with another firm and are you looking for a second opinion on your e-invoicing choice? That is possible too.

Frequently asked questions

Do I really have to switch, or will the government give me more time?

The tolerance period ended at the end of March 2026. Since then, FPS Finance can impose fines on anyone who is not compliant. No new extensions have been announced.

I only sell to private individuals. Do I have to switch as well?

Not for the sales themselves, since B2C does not fall under the obligation. But for your incoming invoices you do need to be able to receive electronic invoices. A basic subscription with a Peppol access point is often sufficient.

Can I also send an invoice to a private individual via Peppol?

Technically yes, but private individuals usually do not have a Peppol connection. For B2C you continue to work with PDF via email or paper.

How do I know whether my client is on Peppol?

Every business with a Belgian VAT number has been on the Peppol network for B2B transactions since 1 January 2026. For foreign customers this varies by country.

Can I still send a credit note by email?

A credit note follows the same rules as an invoice. B2B has to go via Peppol, B2C may continue via email or paper.

What about invoices between two entities of the same group?

Those also fall under the B2B obligation. Invoicing between related entities runs via Peppol.

What if Peppol goes down?

Peppol has very high availability (99.9% and above). In exceptional cases of downtime there is delay, not loss. Invoices are buffered and sent as soon as the system is active again.

Still unsure whether your invoicing is Peppol-ready? Let by Watson check it for you. We review your setup, activate the right connection and confirm that your invoices leave and arrive correctly, so you can put this behind you. Book your check today.