What your invoice must contain
Belgian VAT law lists the details that make an invoice valid. Leave one out and your client's deduction is at risk while you face a correction at the next audit. The list is shorter than its reputation, with one trap: the date of the delivery or the service is the one people forget, and it is the first thing an inspector looks for.
Take the table below and hold it next to your latest invoice. If everything is there, your template is sound and you can stop thinking about it for the rest of the year.
The mandatory details on a Belgian invoice
| Detail |
What you write |
Where it goes wrong |
| Invoice date |
The day you issue the invoice |
Mixed up with the delivery date, while both are required |
| Invoice number |
A sequential number, for instance 2026-014 |
Gaps in the series after a deleted invoice |
| Your details |
Name, address, company number and VAT number |
The VAT number missing from that first year template |
| Client details |
Name, address and VAT number for a business client |
An old address that was never updated |
| Description |
The nature and the quantity of the goods or services |
A description too vague to be checked |
| Date of delivery or service |
The day or the period in which you delivered |
The single most forgotten item of the list |
| Amounts and VAT |
The amount excluding VAT per rate, the rate and the VAT amount |
One total including VAT, with no breakdown |
| Special wording |
« VAT reverse charge » or the exemption scheme, where they apply |
No VAT charged and no reason given either |
If you work regularly for a client abroad, further details apply, such as the VAT number with country code and the reason for the exemption. Have that template checked once by your accountant.
Writing an invoice in five steps
In practice the order never changes. Client first, then the lines, then the VAT, then the number, and sending at the very end. Turn that around and start by picking a number, and sooner or later you end up with a gap in your series.
It sounds like paperwork, yet after three invoices the sequence runs by itself. Decent software enforces that order anyway and fills in most of it for you.
-
Pick the client and check the VAT number in the Crossroads Bank for Enterprises. A wrong number means your Peppol delivery never leaves.
-
Put the work on separate lines, with a description your client can follow alone. « September services » stays too vague, « website design, second instalment » does not.
-
Set the VAT rate line by line: 21 per cent for most trades, 6 or 12 per cent in construction and a handful of sectors.
-
Let the software assign the next number in the series, then fill in the invoice date and the delivery date.
-
Send it, and set the due date and the reminder straight away.
Unsure about a rate? Never invoice at 6 per cent on a hunch. The gap with 21 per cent lands on your desk at the audit, even if the client is long gone by then.
VAT, the small business exemption and reverse charge
Three situations cover almost everything a self employed person runs into. In the ordinary case you charge 21, 12 or 6 per cent and pay it through in your quarterly return. If your annual turnover stays below 25,000 euros and you opted for the small business exemption, you charge no VAT and you say so explicitly on the invoice.
The third case is reverse charge. For construction work supplied to a VAT registered client you charge no VAT and write « VAT reverse charge » on the invoice. Your client then books the VAT both ways. Contractors, electricians and joiners know the mechanism well, and anyone working as a subcontractor meets it too.
What you must not do in any of the three: charge VAT without a VAT number, or pick a rate because the client asked nicely. The price is negotiable, the rate is not.
Under the small business exemption the sentence « Special exemption scheme for small businesses » belongs on every invoice. Without it, it looks as though you simply forgot to charge VAT.
Numbering, deadlines and storage
Your invoices carry an unbroken number, assigned in the order they are issued. Most self employed people restart each year with a series such as 2026-001. That is allowed, as long as no gaps appear and no number is used twice. You never delete an invoice: you issue a credit note that refers back to the original number.
The timing rule fits in one sentence. You issue the invoice no later than the fifteenth day of the month following the delivery or the service. Delivered in March means invoiced by 15 April at the latest, even when the client has paid nothing yet.
Storage runs for ten years, in the form in which the invoice was issued. For an electronic invoice that means the structured file, not only the pdf you printed from it. Software that keeps that archive on its own saves you a folder nobody ever tidies.
Sending your invoice over Peppol
Since 1 January 2026, invoicing between Belgian VAT registered businesses runs on structured electronic invoices over the Peppol network. A pdf by email no longer counts for those, however neat it looks. The structured file drops straight into your client's bookkeeping, which removes the retyping and the typing errors with it.
In daily use, once your software is connected, almost nothing changes for you. You build the invoice as before and click send. The software finds the client through the company number, pushes the document onto the network and shows you the delivery receipt. If the client does not appear in the directory, they are not connected yet and you fall back on the classic route.
If you invoice private individuals only, the obligation does not apply to you. Choosing a tool today that cannot do Peppol is still unwise: the first business client arrives sooner than expected.
-
Your software must be an access point or work with an accredited one.
-
Your company number must be registered in the Peppol directory, otherwise nobody can reach you.
-
Supplier invoices come in through the same channel, ready to be booked.
At Novadesko the Peppol delivery is part of the subscription, with no cost per document. That is not the case everywhere: some vendors charge per invoice sent.
What invoicing software for freelancers must do
Invoicing software for a self employed person is a different animal from an accounting suite for a mid sized company. You do not need twenty modules, you need six things that always work. The rest is sales material.
Test all six during the trial, with your own clients and your own amounts. A demo full of invented data tells you nothing about how it feels on a busy Friday evening.
-
A template with your logo that keeps the legal details complete for you.
-
Peppol delivery included, with a readable status per invoice.
-
Automatic reminders, so you stop tracking by hand who forgot to pay.
-
Recurring invoices for clients on a fixed monthly amount.
-
An export your accountant is happy with, or direct access for them.
-
Comfortable use on a phone, because half the invoices go out between two jobs.
Word, Excel or proper software
As long as you send three invoices a month, a Word template holds up. It starts to hurt when the VAT return comes round, or the day a client asks why they never received a reminder. The Peppol obligation moved that tipping point forward: a document you lay out yourself never reaches the network.
The table compares the three ways of working as they feel in practice, not as they are sold.
Three ways of writing your invoices
| Way of working |
What it does well |
Where it traps you |
| Word or a pdf template |
Available right away and free |
No Peppol, no follow up, numbering entirely by hand |
| Excel with one sheet per year |
A view of the totals for your VAT return |
Formulas that break quietly and no sending at all |
| Invoicing software |
Legal details, Peppol, reminders and archiving in one go |
A monthly subscription and an hour of getting used to it |
Getting paid faster
Between businesses the legal payment term is thirty days, and parties cannot contract beyond sixty. Plenty of self employed people write thirty out of habit when fifteen would pass without comment on smaller amounts. Your term is a negotiating point, not a law of nature.
What pays off is not the term but the follow up. A polite reminder three days after the due date collects the bulk of it. Ring a month later and you are already at the bottom of the pile. Let that run automatically and you win time as well as money.
Put your structured payment reference on the invoice too. Clients pay faster when there is nothing to retype, and your bank statement matches the payment to the right invoice on its own.
If an invoice stays unpaid, you are entitled by law to late payment interest and to a fixed compensation. Mention it briefly in your terms: it makes your reminder sound serious straight away.
Getting your first invoice out tonight
Setting up takes less than half an hour. You enter your company details, upload your logo, choose your number series and create your first client. From there, every following invoice is a matter of clicks.
The fourteen day trial runs without a bank card and without commitment. Use it the way you will use the software afterwards: write real invoices, send one over Peppol and check that the reminder leaves exactly as you set it. If it does not suit you, it simply stops.
Frequently asked questions
Can I write my own invoices as a self employed person?
Yes. Nothing forces you to go through an accountant to invoice. You stay responsible for the legal details, for the correct VAT rate and for keeping the invoices for ten years. Software that enforces those details takes away most of the risk.
What does invoicing software for a freelancer cost in Belgium?
The Belgian market runs roughly from ten to fifty euros excluding VAT per month, depending on the modules and the number of users. Novadesko starts at 19 euros excluding VAT per month, Peppol delivery included and with no cost per document. Always work out the total over twelve months before comparing.
Can I create an invoice for free?
For a handful of invoices a year, a template or a free plan will do. As soon as you invoice other VAT registered businesses you hit the Peppol obligation, which free versions rarely cover. At Novadesko you test for fourteen days without a card, after which a paid subscription takes over.
When do I have to issue my invoice?
No later than the fifteenth day of the month following the one in which the VAT becomes due, so usually the month of the delivery or the service. Deliver in March and the invoice goes out by 15 April at the latest, even if payment has not arrived.
Do I have to send my invoices over Peppol?
Since 1 January 2026, yes, for invoices to other Belgian VAT registered businesses. They have to travel as a structured electronic document over the Peppol network. For private clients a pdf or paper invoice is still allowed.
What do I do about an invoice that went out with a mistake?
You do not delete it and you do not touch the number. You issue a credit note referring to the original invoice number that corrects the amount, then you draw up the correct invoice. Your series stays unbroken, which is the first thing checked at an audit.
How long do I have to keep my invoices?
Ten years, in the form in which they were issued. For an electronic invoice that means keeping the structured file itself. With invoicing software the archiving happens on its own and stays searchable.
Read next
This page summarises the Belgian VAT rules as they stand in August 2026. For your own file your accountant remains the right person to ask, especially with the small business exemption, reverse charge or foreign clients.
