Where to join a social insurance fund in Belgium

Offices in your city, with the visit rules for each

Each fund runs its own branches, and visits are often by appointment, sometimes only by phone or video call. For each office you can see which fund it belongs to, how it receives new members and what to have ready before you call.

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1 office in Mons

  • Mons

    Caisse nationale auxiliaire — Mons

    Rue de la Halle 1, 7000 Mons

    You must join a fund before you start, even for a secondary activity, and the public fund is one option.

    Office website0800 12 018

    Use the current individual affiliation declaration. Prepare national-register and contact details, activity start date, activity description, enterprise number where applicable, and information about other work or benefits. Confirm supporting documents and submission arrangements with the fund; downloading the form is not affiliation.

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Where to next

Social security for the self-employed

If you are about to start your own activity in Belgium, this explains the fund you must join, your free choice between funds and where you can visit one.

Social security registration in Belgium

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