Advance invoices in Belgian practice and Peppol

When to issue a Belgian advance or deposit invoice, how to settle it on the final invoice, and how credit notes interact once the advance has already gone out on Peppol.

Updated

  • Belgium

One job: treat advances as real invoices

A Belgian advance / deposit invoice is a VAT invoice, not a renamed quote. It opens a receivable, uses your invoice sequence, and (when required) travels as a Peppol BIS Invoice. Relabelling a quote as “deposit” without a proper invoice leaves both parties without clean VAT evidence.

Document roles: Invoice, credit note, and quote. Lifecycle gates: Quote to invoice workflow.

When to invoice an advance

SituationIssue an advance invoice?Notes
Deposit due on quote acceptance / signatureYesContract or commercial terms should state the amount or %
Progressive billing by signed milestoneOften a milestone invoice (same discipline)Align lines to the signed milestone, not the full quote
Cash received with no invoice yetCatch up with an invoiceReceipt alone is not a substitute for the VAT document
Pro forma / payment request onlyNoPro forma is not a tax invoice and is not Peppol billing

VAT timing on advances follows Belgian rules for your regime (standard, reverse charge, and so on). Map the same category you would use for the underlying supply; see Belgian VAT regimes.

What a good advance invoice contains

FieldWhy
Own invoice number (gap-free series)Advances burn real numbers; do not reuse quote codes
Clear description (“Advance on …”, project / quote ref)Buyer AP and your final settlement need a trail
Taxable base, VAT (or AE / exempt as applicable), totalSame quality as any other invoice
Parties, VAT IDs, datesLegal mentions checklist

Send it on Peppol when domestic B2B structured e-invoicing applies; see the 2026 obligation.

Final invoice settlement

On completion (or the last milestone), the final invoice bills the remaining balance. It must not silently re-invoice the full contract as if no advances existed.

PatternCorrectWrong
SettlementFinal invoice = total due − advances already invoiced (shown clearly)Final invoice for 100% with a verbal “ignore the advances”
ReferencesQuote / project + prior advance invoice numbersNo link to advances already on Peppol
TotalsOpen balance matches what the buyer still owesDouble-counting advances in AR

Present the deduction so PDF and structured data stay consistent, with coherent tax categories for each amount.

Credit notes and advances

Once an advance is sent on Peppol, you do not edit it. Wrong amount, cancelled project, or over-advance: issue a structured credit note referencing that advance invoice, then a corrected advance or an adjusted final invoice if needed. Mechanics: Credit notes on Peppol.

EventAction
Advance too high / project cancelledCredit note on the advance (full or partial)
Scope change before finalCredit / re-invoice advance if VAT base changes; else adjust only the final
Final overstates after advancesCredit the final; do not rewrite the advance history
Advance invoice

A formal VAT invoice for a deposit or instalment before (or during) the full supply. It uses the invoice sequence and, when required, Peppol; it is distinct from a quote or pro forma.

Advance invoices in Belgian practice and Peppol · OrdoGrid