Belgium Moving and Relocation Guide

Municipal Registration and National Register

• Arrival registration (within 8 working days): Within 8 working days of arrival in Belgium, every new resident must register at the municipality (the "gemeente" / "commune") of their residence. The registration requires: (a) a valid passport or national identity card, (b) proof of residence (a rental contract or property deed — the "huurcontract" / "bail de location" or "akte van eigendom" / "acte de propriété"), (c) the "model 8" / "formulier 8" — the arrival declaration form (issued by the municipality upon registration), (d) a recent utility bill or bank statement showing the Belgian address. The municipality issues the rijksregisternummer / numéro de registre national (the national register number) — this is a unique 11-digit number used for all tax, social security, and administrative interactions. EU/EEA nationals receive a E-kaart / carte E (the electronic residence card for EU citizens). Non-EU nationals receive a vreemdelingenkaart / carte d'étranger (the A-card or B-card for temporary/permanent residence).
• Tax registration (FOD Financiën / SPF Finances): After the municipal registration, the taxpayer must register with the FOD Financiën / SPF Finances for tax purposes. The registration is automatic for most new residents — the municipality shares the data with the tax authorities via the BRP. However, the taxpayer should: (a) file an arrival declaration (aangifte van aankomst / déclaration d'arrivée) with the FOD Financiën — this confirms the Belgian tax residence date and the start of the partial-year tax period, (b) obtain a tax file number (kohiernummer / numéro de rôle) — the 12-digit tax reference number used on all tax correspondence. The tax file number is printed on the first tax assessment (aanslagbiljet / avertissement-extrait de rôle).

Social Security Enrolment

• RSZ/ONSS registration: Employees working in Belgium must be registered with the Rijksdienst voor Sociale Zekerheid (RSZ) / Office National de Sécurité Sociale (ONSS) — the Belgian social security institution. The employer handles the registration through the DIMONA declaration (the "Déclaration Immédiate — ONSS" — the immediate electronic notification of employment). The employee must also: (a) choose a health insurance fund (ziekenfonds / mutuelle) — the publicly mandated health insurance: the Christelijke Mutualiteit / Mutualité Chrétienne, the Socialistische Mutualiteit / Mutualité Socialiste, the Liberale Mutualiteit / Mutualité Libérale, the Neutrale Ziekenfonds / Mutualité Neutre, or the Hulpkas voor Ziekte- en Invaliditeitsverzekering (HZIV) / Caisse Auxiliaire d'Assurance Maladie-Invalidité (CAAMI), (b) register for a pension fund — the Rijksdienst voor Pensioenen (RVP) / Service Fédéral des Pensions (SFP) handles the state pension accumulation. The social security contributions (the "sociale bijdragen" / "cotisations sociales") are approximately 13.07% for employees and 27–30% for employers (on gross salary).
• Cross-border social security (EU Regulation 883/2004): If the new resident works in Belgium but lives in a neighbouring country (France, Netherlands, Germany, Luxembourg), the social security is governed by EU Regulation 883/2004. The general rule: an employee is subject to the social security of the country where the work is performed. The frontier worker exception: a person who works in Belgium and lives in a neighbouring country is subject to the social security of the home country — as long as the employee works from the home country for at least 25% of the time (the telework facilitation arrangement).

Bank Account and Practical Steps

• Opening a Belgian bank account: A Belgian bank account is essential for salary payments, utility bills, and tax refunds. The major Belgian banks are: KBC, BNP Paribas Fortis, ING Belgium, Belfius, and Argenta. Opening an account requires: (a) a valid passport, (b) the national register number, (c) proof of Belgian residence (the rental contract or utility bill), (d) the employment contract (for salary account). The IBAN format for Belgian accounts is BE + 2 digits + 12 digits (e.g., BE68 1234 5678 9012). The Belgian bank account is used for the doorlopende machtiging / domiciliation automatique / prélèvement automatique (direct debit authorisations) for utility bills, insurance, and mortgage payments.
• Tax implications of arrival year: The year of arrival in Belgium results in a partial-year tax period. The taxpayer must: (a) file a split tax return — one for the period as a non-resident (before the Belgian arrival date) and one as a resident (from the Belgian arrival date), (b) report worldwide income only for the period of Belgian residence, (c) apply for the expat tax regime (if eligible — see the Expat Tax Regime Guide) within 3 months of the first Belgian payroll inclusion, (d) claim the personal allowance (belastingvrije som / quotité exonérée) prorated to the period of Belgian residence. The arrival date is the date of registration in the BRP (the municipal register), not the date of the employment contract or the first day of work.

For the full expat tax regime rules, see our Expat Tax Regime Guide →. For the cross-border employment and social security rules, see our Cross-Border Tax Guide →. For the personal income tax framework for residents, see our Personal Tax Guide →.