Recurring invoices in Belgium: subscriptions, retainers and Peppol

A subscription, a maintenance contract or a monthly retainer is billed with a new invoice for every period: a new number, the period covered, the current price and a separate transmission. The invoice must be issued by the 15th of the month after the period ends. Since 1 January 2026 it must be a structured e-invoice, normally over Peppol, when you are established in Belgium and the customer is a business established in Belgium with a Belgian VAT number (a foreign business with only a Belgian VAT registration is out of scope). A reduction for a period already invoiced goes through a credit note that refers to that invoice; an increase goes on an extra invoice.

This guide is for Belgian businesses and freelancers who bill customers at regular intervals, and for their accountants. Billing a month of days worked is covered in Invoice your client for a month of freelance work; numbering in Invoice numbering in Belgium.

What the law requires for each period

Due date, IBAN, structured communication and purchase order are not VAT mentions. Peppol requires a buyer or order reference: OrdoGrid fills the buyer reference with the purchase-order number, else the structured communication, else the invoice number.

When VAT becomes chargeable: in advance, in arrears, upfront

Services billed through successive statements or payments are treated as performed at the end of each period they cover (art. 22 §2 VAT Code). Since 1 January 2016, for services you must invoice, VAT becomes chargeable when you issue the invoice, before or after the period; on the payment, for the amount received, if the customer pays before the service is performed; at the latest on the 15th of the month after the period (art. 22bis §1, Law of 6 December 2015).

Chargeability (exigibilité, opeisbaarheid)

The moment the VAT becomes owed to the State and must be reported in a VAT return. It can differ from both the service date and the payment date.

In practice, VAT on a period invoice to a Belgian business falls in the return covering the invoice date, unless the customer paid first. We recommend sending each invoice on the date it carries; ask your accountant how early payments are reported.

Plan changes, cancellations and indexation

A sent invoice is never edited; OrdoGrid locks its amounts once sent over Peppol or paid. Future changes go on the next invoice; changes to an invoiced period need a credit note, or an extra invoice when the customer owes more.

Prorating. Follow your contract; a common method is per day: the price difference, times the remaining days, divided by the days in the period. Write the calculation in the credit-note line. We recommend a credit note over a negative line on next month's invoice, so the correction refers unambiguously to the invoice it corrects.

Check the customer on Peppol every period

OrdoGrid has no Peppol ID field on clients: each time you open Envoyer (Send), it looks the customer up again from the invoice's VAT number, under 0208 (enterprise number) and 9925 (VAT number). A customer reached in July can be missing in October: it is moving to another Peppol provider and the new registration is not live yet, it ended its registration, the client record's VAT number now has a typo, or you now invoice another legal entity after a restructuring (an enterprise number never changes; a new entity is a new client).

Causes and checks: Find a customer on Peppol.

Run each period in OrdoGrid

A recurring invoice creates each period's invoice on the planned day and, by default, sends it to the client: through Peppol if they are registered, otherwise by email. You can also have it create drafts, which you review and send yourself. It is included in the Starter and Business plans. Without one, you duplicate last period's invoice.

Set up a recurring invoice

1. In Invoicing, open Recurring invoices and click New recurring invoice: the invoice editor opens with Make recurring already ticked in the Recurrence group of the Summary panel. You can also tick Make recurring on a new invoice, or start from an existing invoice: open it from Invoices and click Make recurring in its side panel; its client, lines and notes are copied.
2. Pick the client with Select a client and add the lines as on an invoice. Write {period}, {month} or {year} in a line or in the Notes: they are replaced by the billed period. Support Pro, {period} becomes "Support Pro, 01/10/2026 – 31/10/2026", and Support Pro, {month} becomes "Support Pro, October 2026" in English documents. The French spellings {periode}, {mois} and {annee} work too. Each invoice uses the details stored on the client record and on your company: on a recurring invoice, they are not edited in the document.
3. In Recurrence, enter a Template name (it does not appear on the invoice), choose the frequency in Every (for example 1 month, 3 months, 1 week, 1 year or 10 days), the First invoice on date, what Each invoice covers: The period that starts (billed in advance) or The period just ended (in arrears), then the Payment terms (days). A first invoice on the 31st falls on the last day of shorter months, then returns to the 31st.
4. Under End, keep Never, or stop On a date or After a number of invoices.
5. Under When created, choose Send it automatically or Create a draft to review. Sending follows the rule of the Envoyer (Send) button: through Peppol if your company has signed the Peppol authorisation and the client is registered, otherwise by email to the address on the client record.
6. If the client record requires a purchase order, enter the Purchase order no. under Documents and references: it is repeated on every invoice. If it changes every period, update it on the recurring invoice before the due day, or on the draft.
7. The document shows the next invoice: its date and due date follow the schedule and are not typed; the number (the document and the preview show "Assigned when created") and the structured communication are assigned when each invoice is created. No payment is recorded here either: each invoice is settled on its own. Your company name can be changed for this template; your other details (address, VAT, IBAN…) are read from the company settings at each invoice, so they stay up to date. Preview next invoice shows its PDF, with the variables filled in. Then click Create the recurring invoice: the first invoice is created on its date, unless you ticked Create the first invoice now: it is then created straight away, dated today.

On the planned day, around 6 am Belgian time, OrdoGrid creates the invoice: the next number, today's date, the due date from Payment terms (days) and a new structured communication. The service is dated the day of the invoice; if you choose The last day of the period under Delivery / service date in Recurrence, that day is added in Date de livraison / prestation (date of supply) when it differs from the invoice date. If the recurring invoice sends automatically, the invoice leaves at once, in a single attempt. The company's owners and administrators get a summary email: sent through Peppol, sent by email, or a draft to send. A missed due day, during an outage for instance, is created on the next run, dated the day it is created; each period stays a separate invoice.

A send that cannot go out is never tried again: the invoice stays a draft, the recurring invoice's page shows the reason and the next invoices carry on. That happens for a client without an email address, the monthly Peppol quota reached, a Peppol send refused or uncertain, or a client with a Belgian VAT number not found on Peppol: a Belgian business must receive a structured invoice, so OrdoGrid does not email it instead. Open the draft, check it, then send it with Envoyer (Send). The Status column of the invoices created shows which ones went out.

A recurring invoice pauses itself when it cannot create the invoice: client deleted, company IBAN missing, purchase order now required by the client, or a plan without recurring invoices. The page shows the reason; fix it, then click Resume. The periods of a pause are not caught up: the next invoice is the first due day from today. Create the next one now creates the next due invoice straight away, dated today; End stops the recurring invoice. To change it, open it from Recurring invoices: the same editor shows the next invoice, with these actions at the top of the page and the invoices already created below; click Save. Editing the recurring invoice never changes invoices already created; a new schedule starts again from its first invoice date.

Review and send the period invoice

1. If the recurring invoice creates drafts, or a send could not go out, open the Brouillon (draft) from the summary email or from the list of invoices created on the recurring invoice's page. Without a recurring invoice: in Factures (Invoices), open last period's invoice and click Dupliquer (Duplicate) in its side panel. On the list row the action follows your interface language.
2. A Brouillon (draft) opens, dated today, with the next number in N°. It keeps the client, lines, Options de TVA, discounts and Notes; it drops the N° bon de commande (purchase-order number) field, attachments and the old structured communication (Communication is refilled from the new number). If the client uses purchase orders, last period's purchase-order line (by default PO: …) stays in Notes until you type the new number, which replaces it. The number is committed at the first save.
3. Set Échéance (due date) to your contract's term; OrdoGrid proposes 30 days.
4. Update each line: Description with the new period ("Support Basic, 1–31 October 2026"), Quantité for seats, Prix Unitaire after a change. There is no service-period field, and OrdoGrid's Peppol invoice carries none, so the description states the period. Also add the period's last day with Delivery / service date (Date de livraison / prestation on French documents), below Échéance in the Récapitulatif panel, unless it is the invoice date: OrdoGrid prints it on the PDF and sends it on Peppol as the delivery date.
5. Under Documents et Références, enter this period's N° bon de commande (purchase-order number); the field is shown when the client record has Exiger un bon de commande pour les factures ticked; otherwise open it with Ajouter un N° bon de commande (add a purchase-order number). Attach any usage report as PDF, PNG, JPEG, CSV or XLSX, within OrdoGrid's 2 MB total per document: attachments go into the Peppol message by default, and Peppol accepts no DOC, DOCX, XLS or GIF (Peppol attachment types).
6. Keep the Communication OrdoGrid fills in from the proposed number. If you change the number in N°, empty Communication: at save, OrdoGrid rebuilds it from the final number. One reference per invoice, never one per customer (structured communication).
7. Check Aperçu du PDF (PDF preview), then Enregistrer (Save).
8. Click Envoyer, read the Peppol block, untick Email unless the customer wants a copy, and click Sauvegarder & Envoyer once.
9. In Peppol → Outbox, click Vérifier (Check): Traité means network delivery, not acceptance or payment. When paid, use Record payment in Settlement. From the start of the due date, an unpaid invoice moves from Envoyée (sent) to En retard (overdue), although a payment that day is still on time; reminders are up to you.

Credit a change during a period

1. In Factures, tick the period invoice and click Note de crédit.
2. The credit note copies client, lines and VAT treatment, shows the original under Facture d'origine and proposes the next number (NC-2026-0001 and so on).
3. Before you save, replace the line with the prorated difference, as a positive amount (from the first save a credit note's amounts are locked, and a credit note linked to an invoice can never be deleted). Put the reason in Notes, which print on the PDF and travel in the Peppol XML as the document note (BT-22). OrdoGrid adds the VAT refund mention described in Correct or credit an invoice itself when the credit note refunds Belgian VAT to a customer with a VAT number.
4. Save and send it like the invoice: Envoyer, Peppol ticked, Sauvegarder & Envoyer.
5. The credit reduces that invoice's balance, not next month's. If it was paid, Settlement shows Refund due: refund the customer, then click Record refund.

Stripe recurring payment links are not invoices

Under Payment links (page Liens de paiement), a Nouveau lien (new link) of type Récurrent (recurring) sets up a monthly or annual card subscription on your own Stripe account. It is not tied to an invoice: it creates none, sends nothing over Peppol and records no payment on an invoice. Business customers still need an invoice per period.

If your own system runs the schedule

Your billing system can create each period's invoice through the public API. Give each contract period its own external_id, such as sub-1042-2026-10, so a retry never creates a second invoice; omit number to get the next one. Check the customer with GET /api/v1/peppol/participants/{vat_number}, send with POST /api/v1/peppol/invoices/{invoice_id}/send, and after a timeout use GET /api/v1/invoices/lookup?external_id=… before retrying. There is no test mode (Public API integration).

Worked example: a monthly plan with a mid-month downgrade

Hexalink SRL, an IT support company in Liège, issues its documents in French. Fiduciaire Lemaire SRL in Namur (enterprise number 0563.847.241, on Peppol as 0208:0563847241) pays €120.00 a month excluding VAT for "Support Pro", billed in advance on the 1st and payable within 30 days. The contract prorates plan changes per day and credits a downgrade on the current month's invoice. Hexalink's series is shared with other customers, hence the gaps in the numbers.

1. Each invoice goes out over Peppol on the date it carries, so the VAT on each becomes chargeable on that date.
2. On 15 September the customer asks in writing for "Support Basic" (€80.00) from 16 September: €40.00 a month less, for 15 of 30 days, comes to €20.00 plus €4.20 VAT.
3. Hexalink creates NC-2026-0020 from F-2026-0150 with Note de crédit, with the reason in Notes and the calculation in the line, and sends it over Peppol. OrdoGrid adds the mention "T.V.A. à reverser à l'Etat dans la mesure où elle a été initialement déduite" itself, because the credit note refunds Belgian VAT to a customer with a VAT number. Its accountant regularises the €4.20 in the current return, not by amending an earlier one.
4. F-2026-0150 now shows €121.00 outstanding (€145.20 − €24.20, or €100.00 plus 21%). The customer pays it on 28 September with +++002/0260/15051+++; Record payment turns the invoice Payée (paid).
5. On 1 October Hexalink duplicates F-2026-0150, not the credit note, changes the line to Support Basic at €80.00, enters 31 October 2026, the last day of the period, in Date de livraison / prestation and sends F-2026-0160 (communication +++002/0260/16061+++).

Variant: an annual plan invoiced upfront

The customer also buys a backup licence at €1,440.00 for 1 October 2026 to 30 September 2027, invoiced on 25 September 2026 as F-2026-0158: €1,440.00 plus €302.40 VAT, €1,742.40. VAT on the whole year becomes chargeable on 25 September, the invoice date (or the payment date, had the customer paid first). The contract refunds unused full months: a cancellation from 1 April 2027 gives a credit note for six months, €720.00 plus €151.20 VAT, €871.20, referring to F-2026-0158.

Edge cases and common mistakes

Evidence to keep

What the law requires. Keep each invoice and credit note for seven years from 1 January after the year of issue (art. 60 VAT Code, Law of 18 December 2025), authentic, intact and legible.

What we recommend. Per customer: the contract and amendments, including indexation and proration rules; each written change request with its effective date; purchase orders; the PDF and XML of every invoice and credit note from Peppol → Outbox, with the Traité date; and the customer's written confirmation whenever it could not receive over Peppol.

What OrdoGrid does. It archives the exact XML and PDF of every Peppol transmission, and Settlement keeps the Original document. It is not a legal archive and guarantees no retention period: download the Outbox ZIP to your own storage regularly.

FAQ

Can OrdoGrid create my recurring invoices automatically?

Yes, on the Starter and Business plans: a recurring invoice creates each period's invoice on the planned day, with the period in its lines, and sends it through Peppol if the client is registered, otherwise by email. If you prefer to review first, choose Create a draft to review, then send each invoice with Envoyer (Send). You can still duplicate last period's invoice, or create invoices from your own system through the public API.

By when must I issue a monthly subscription invoice?

By the 15th of the month after the period, so by 15 October for September. If the customer paid first, by the 15th of the month after the payment (Royal Decree no. 1, art. 4).

When is VAT due on a subscription billed in advance?

For a Belgian business customer, when you issue the invoice, or earlier if the customer pays first (art. 22bis VAT Code, since 1 January 2016). For a business customer in another EU country, at the end of each period or on an earlier payment.

How do I handle a mid-month downgrade?

Credit that month's invoice for the prorated difference, for example €40.00 × 15 ÷ 30 = €20.00 plus €4.20 VAT, send the credit note over Peppol, and bill the new price from the next period.

Should the structured communication stay the same every month?

No. Each invoice gets its own reference, so every payment matches one invoice. Reuse a reference only in reminders for that same invoice.

My customer was on Peppol last month but not now. What do I do?

Check its enterprise number on lookup.peppol.org and ask the customer. If it technically cannot receive, email the same invoice by the deadline; never create a second one.