Step 2 of 4 · ProjectsBy jurisdiction

6 open source tax projects for Belgium.

Every project on the list for Belgium, grouped by kind. Global tools have a page of their own. Entries without a warning come first in each group; the labels mark what to check.

6 projects6 maintained5 on the map19 jurisdictions + globalFacts checked 6 Oct 2026

Browse these by tax area

Income tax Corporate tax VAT & indirect

Calculators

1 project

Small tools that compute one tax for one country.

Tax-Calculator (jdspr)React calculator for Belgian self-employed: INASTI contributions, income tax (IPP), VAT and expenses.CalculatorBEFor individual taxpayersLicence unknown

APIs

3 projects

Validation, rates, filings and registries you can call directly.

BelgiumVatChecker.NET Web API that validates Belgian and EU VAT numbers using the VIES service.APIBE · EU

peppol-billingTypeScript library that generates and parses Peppol BIS Billing 3.0 (UBL 2.1) invoices and credit notes.APIBE · EU

ubl-peppolPHP library that builds UBL 2.1 e-invoices for Peppol BIS Billing 3.0.APIEU · NL · BE

Automations

1 project

Reusable workflows for provisions, reconciliations and compliance runs.

OCA l10n-belgium (Odoo)Odoo localisation for Belgium: MIS Builder templates for the VAT declaration, P&L and balance sheet.AutomationBE

Tax datasets

1 project

Rates, treaties and statistics, open and versioned.

myTransferPricing referenceSummaries of 18 OECD transfer pricing country profiles, with a prompt that reviews a Local File against one.Tax datasetAT · BE · BR · DK · FR · DE · GR · IE · IT · LU · NL · PL · SG · ES · SE · CH · UK · US

Labels mark what to check before you rely on an entry: inactive or archived code, demos, paid services and unclear licences. Only maintained projects for companies and tax authorities appear on the map. Search and filter the whole list.

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Next · Step 3 of 4The gapsThe activities with no open project yet, and the partly covered ones, with what to build on.