Everything in Belgium hangs off one chain: commune registration triggers the police visit, which triggers your national number and eID — and without those, banks, health funds and employers all stall.
Overview
Belgian administration is built around the commune (gemeente/commune) and the National Register. Whatever permit you arrive on, your first statutory obligation is to present yourself at the town hall of the municipality where you will live within 8 working days of arrival — for long-stay arrivals this starts your registration in the foreigners' register (vreemdelingenregister / registre des étrangers). A neighbourhood police officer (wijkagent / agent de quartier) then physically verifies that you live at the declared address; only after a positive residence check are you registered and assigned your national register number (rijksregisternummer / numéro de registre national), the 11-digit key to everything else: your electronic residence card, employment payroll, the health insurance fund (ziekenfonds/mutualité) you must join, banking, and the itsme digital-identity app that unlocks government portals. Because work migration, integration duties and even acceptable document languages differ between Flanders, Wallonia and Brussels, where you choose to live changes your obligations, not just your commute. Verified against ibz.be, dofi.ibz.be, diplomatie.belgium.be and the regional portals as of June 2026.
Before Departure — Documents and Approvals
- Authenticate civil-status documents at origin: Birth and marriage certificates need an apostille (Hague countries) or legalisation chain in the issuing country, plus sworn translation into Dutch, French or German (region-dependent) unless an EU multilingual standard form applies. The commune will want these when registering your civil status.
- Criminal-record extract and medical certificate: Long-stay (visa D / single permit) files need a criminal-record certificate if you are over 18, legalised and translated, and the standard medical certificate from the annex to the Law of 15 December 1980 — both no more than 6 months old at filing.
- Visa D collection: If your single permit or other long-stay authorisation is approved while you are abroad, collect the visa D at the Belgian embassy with your passport and the positive decision (Annex 46/47). Entry B34 on the visa marks a single permit, B29 an EU Blue Card.
- Health cover for the gap: Mutualité membership only starts once you are registered and (for employees) contributing — carry travel/expat health insurance covering the first weeks. Proof of all-risk health insurance is itself a single-permit file requirement.
- Know your region's obligations: Settling in Flanders triggers the inburgering civic-integration duty for most non-EU newcomers; Wallonia has the parcours d'intégration; Brussels has its own mandatory welcome programme. Where you sign your lease decides which regime binds you.
Continue reading — paid members only.
This guide is part of our full paid membership library. Upgrade to access all 10 Belgium guides, plus Migration Fee Protection up to USD 25,000 if your application doesn't go ahead for a qualifying reason.
See Paid Plans →Frequently Asked Questions
What exactly must I do within 8 working days of arriving in Belgium?
Present yourself at the town hall of the municipality where you will live. Long-stay arrivals (visa D, single permit) ask for registration in the foreigners' register; the commune opens your file and orders the residence check. Even short-stay visitors not staying in a hotel are required to file a declaration of arrival within a few working days. Bring your passport with visa, proof of address (lease), and your authenticated civil-status documents. The 8-working-day clock is statutory — communes log the date, and late registration can complicate your permit, your start date at work and your health-fund enrolment.
What is the police residence check and what if I miss the officer?
After you report to the commune, the neighbourhood police officer (wijkagent/agent de quartier) visits your declared address to verify you genuinely live there — checking your name on the doorbell or letterbox and usually speaking to you or a housemate. Only a positive report lets the commune register you and issue your national register number. If you are out, the officer typically leaves a notice or returns; persistent failure leads to a negative report and refusal of registration. Make the address visibly yours (name on the letterbox immediately) and respond promptly to any notice — the whole eID chain waits on this step.
What is the national register number and why does everything ask for it?
The rijksregisternummer / numéro de registre national is an 11-digit personal identifier whose first six digits encode your date of birth. It is assigned when the commune registers you and is the key your employer's payroll declaration (DMFA), the tax administration, your ziekenfonds/mutualité, banks and government portals all use to identify you. Before registration, people working in Belgium without living here are identified by an equivalent BIS number from the Crossroads Bank for Social Security, which employers can request via BelgianIDpro. The number appears on your residence card; with the card and a reader — or the itsme app — it becomes your digital login everywhere.
How do I get Belgian health insurance after arrival?
Belgium's compulsory health insurance is administered by health funds (ziekenfondsen/mutualités) you choose and join yourself — it does not happen automatically. Once you have your national register number and have started employment (or self-employment with social contributions), enrol with a fund of your choice or with the public auxiliary fund (HZIV/CAAMI). The fund issues the stickers/digital registration that make doctors' visits and pharmacy purchases reimbursable, typically covering the bulk of standard tariffs. Most people add the fund's modest complementary insurance, and many add hospitalisation insurance privately or via their employer. Posted workers who stay in their home social-security system cannot join and need private cover.
Does it matter administratively whether I settle in Flanders, Wallonia or Brussels?
Yes, more than in almost any other European country. Your region determines: which authority handles your work authorisation and at what salary threshold; whether you fall under the Flemish inburgering duty, the Walloon parcours d'intégration or Brussels' mandatory welcome programme; the language of schooling and of commune correspondence; and which diploma-recognition body (NARIC Vlaanderen vs Equivalences FWB) assesses your qualifications. Even within Brussels, you choose between Dutch- and French-language integration tracks and school systems. Check the regional consequences before signing a lease — a move of a few kilometres across a regional border can change your obligations and your family's schooling options.
How long until I'm fully set up — card in hand, bank, health fund, digital ID?
A realistic span is six to ten weeks. Week 1: commune declaration (statutory 8 working days). The police residence check follows within days to a few weeks depending on the commune's workload. Registration and the national register number come straight after a positive check; the biometric residence card then takes roughly two to three weeks to produce and requires a collection appointment. Banking can start on your passport early on; the ziekenfonds needs your national number; itsme activation needs your eID or Belgian bank credentials, so it lands last. Big-city communes (Brussels municipalities, Antwerp, Ghent) run slower on appointments — book everything as early as the system allows.