Faxing ONEM or CAPAC: what still works

Short answer: when it comes to unemployment, Belgium splits the work between two roles. ONEM (Office national de l'emploi, the National Employment Office) decides on entitlement to benefits and imposes sanctions; a payment institution — CAPAC, the public one, or one of the three trade unions — files your claim and pays you. A document sent to the wrong one of the two does not find its way across on its own. Fax no longer has any official role in this circuit: the control card, the forms and the supporting documents go through your payment institution, through eBox or over the counter. Fax retains one residual, targeted use: reaching a regional ONEM office or a local secretariat when a deadline is running and your contact confirms it is acceptable, with a transmission report kept on file.

FaxTelecom sends faxes from a browser to landlines in seven countries: Belgium, France, Germany, Spain, Italy, Portugal and Canada. The service does not assign a number and does not receive faxes: it covers sending, not receiving. The information quoted here is taken from the institutions' official publications; always check the exact channel with the office handling your file.

Two desks, two roles: the mistake that costs weeks

Many delays in an unemployment file are not caused by a missing document, but by a document that reached the right place… at the wrong institution. The ONEM website sets out the division clearly: the Office rules on eligibility, sanctions, exemptions and special schemes; the payment institution receives your claim, calculates the amount and pays it out.

CAPAC (Caisse auxiliaire de paiement des allocations de chômage, the Auxiliary Fund for Payment of Unemployment Benefits) is the public institution: it pays those who are not members of a trade union. It has its own regional offices, opening hours and contact mailboxes, described on capac.fgov.be. The three union-run institutions (FGTB, CSC, CGSLB) play exactly the same role for their members.

Practical consequence: before sending anything, ask yourself a single question — who decides on what I am asking for? An exemption, a sanction, eligibility: ONEM. An amount, a payment, a certificate: payment institution.

What can no longer be faxed at all

Three families of documents have now left the fax channel entirely, and insisting gets you nowhere.

The control card

The control card (the well-known C3) is filled in day by day and handed to the payment institution after the end of the month. For several years ONEM has been promoting the electronic eC3 control card, usable on a smartphone and accessible through strong authentication (itsme or eID). A fax of a paper card has no value: the signed original is what is expected — or its validated electronic version.

If you are still using the paper version, bear in mind that blue or black ink, initialled corrections and the absence of correction fluid matter more than the quality of a fax copy. A black archival ballpoint pen remains, here, the most reliable tool.

The claim for benefits

It is filed with the payment institution, which checks your identity and the supporting documents. No institution will open an entitlement file on the basis of a fax: identification is the heart of the file, and it goes through the electronic identity card or an appointment.

Incoming decisions and notifications

In the other direction, the Belgian federal authorities now push their letters to eBox, the citizen's official mailbox. ONEM notifications appear there for anyone who has activated it. If you still receive everything on paper, see our article eBox or fax: replying to Belgian authorities: it sets out what eBox really replaces and what it does not, namely the outbound sending of free-form documents.

Where fax still has a real use

Fax is not dead in secretariats: it has become a backup channel. Three situations still justify it.

1. A deadline about to expire and only one reachable contact. You have an unemployment office on the phone, the officer confirms they can pick up a fax within the hour and add it to your file. That is a strong case: sending is immediate, the transmission report timestamps the delivery, and you then duplicate it through the official channel.

2. An additional document requested by a named officer. A missing employer certificate, a medical certificate, proof of address. Fax works when the document is short, when it completes a file that is already open and when you note the officer's name on the cover sheet.

3. A send to a third party in the circuit. An employer, a payroll office, a local union branch, an HR department that has to issue you a C4 or a holiday certificate: these organisations often still accept faxes, sometimes more readily than an email with an attachment.

In all three cases, the number is not something to guess. We do not publish fax numbers of Belgian institutions here: look it up on the page of the relevant office on the ONEM or CAPAC website or your union's head office, and confirm it by phone before sending. Our check a fax number tool at least validates the format of the Belgian number before you hit send.

The cover sheet that gets the document to the right office

An unemployment fax is rarely lost on the line: it gets lost in a paper tray. The cover sheet is what gets it out again. The useful details, for this particular circuit:

• Your file number or, failing that, your national register number (NISS) — that is the search key in every Belgian system;
• The exact office: "ONEM – unemployment office of …" or "CAPAC – office of …", with the department and, ideally, the officer's name;
• The nature of the document in one line: "employer certificate – August 2026 period", not "document";
• The reference of the letter you are replying to and its date;
• The number of pages, cover sheet included, and a phone number where you can be reached.

Our fax cover sheet generator produces a clean cover page from a few fields, and the article Fax cover sheet: the details that get your document to the right office explains why every line counts. A smudge-resistant highlighter over the file reference on your own original also helps on the day you pull the file out again six months later.

Proof: what a transmission report is worth in a social security dispute

This is the point that really matters when a sanction lands or a payment goes missing. Three levels need to be distinguished.

Level 1 — the transmission report

The report generated by the service or by the machine shows that a connection was established with a given number, at a given time, for a given number of pages. Under Belgian law it is a freely admissible item of evidence, weighed by the judge: it does not create a legal presumption the way registered mail does. But it is far from negligible against an authority claiming to have received nothing.

Level 2 — the consistency of the bundle

A report on its own is not very convincing; a report backed by a noted phone call, an officer's name, a confirmation email and a copy of the document sent is far more persuasive. Build that bundle the same day, not three months later. Our pages fax delivery confirmation and fax as legal evidence in Europe set out what each item contributes.

Level 3 — the channel that starts or stops a deadline

For genuinely sensitive acts — an appeal against an ONEM decision before the labour court — fax is not the right vehicle. The appeal is lodged in the forms laid down by the Judicial Code, and the deadlines are short. Our article Faxing a Belgian court: deadlines, e-Deposit and proof of sending explains why Belgian courts now point you to e-Deposit and filing with the registry.

Simple rule: fax to speed things up, the official channel to make them secure. Never one without the other when a deadline is at stake.

Real-life cases, step by step

You have just lost your job

1. Ask your employer for the C4. If they drag their feet, a fax to the HR department, with acknowledgement requested by phone, often unblocks the situation faster than an email.
2. Make an appointment with your payment institution (CAPAC or trade union) to file the claim. That is where the start date of your entitlement is decided.
3. Register as a jobseeker with the competent regional service — Forem, Actiris or VDAB depending on your region.
4. Activate eBox so you receive decisions without postal delay.

An officer asks you for a document with an eight-day deadline

1. Write down the officer's name, the department, the reference and the due date.
2. Ask explicitly: "may I send it to you by fax today, and to which number?" If the answer is no, do not improvise.
3. Prepare the PDF properly: black on white, A4, no greys. Our guide Preparing a PDF for fax helps you avoid documents that arrive unreadable.
4. Send it, download the report, file it with the copy of the document.
5. Duplicate through the official channel within 48 hours, mentioning the fax you sent and its timestamp.

You are challenging a decision

Do not send a fax as an act of appeal. Seek advice from your payment institution or a legal service, then use the prescribed route. At most, a fax can serve to transmit an additional document to a file that has already been lodged, at the request of the registry or the office.

Scanning properly what you send

Half the faxes that "never arrive" do in fact arrive, but unreadable. Three habits:

• Scan, don't photograph. A compact flatbed scanner gives a uniform white background; a smartphone photo brings shadows that the fax's black-and-white thresholding turns into blotches.
• 200 to 300 dpi, black and white or greyscale, then export to PDF. Beyond that you gain nothing: fax caps out at 204 × 196 dpi.
• One page = one page. No double-sided content printed on a single sheet, no stapled annexes photographed at an angle.

For social security files that stretch over months, one A4 elastic folder per institution — one for ONEM, one for the payment institution — avoids the single catch-all file where everything gets mixed up. Digital archiving follows the same logic: our pages archiving your faxes and Proving a fax was sent: reports, confirmations and archiving describe a folder structure that holds up over several years. A 2.5-inch external hard drive is enough for the offline backup copy.

Data protection: an unemployment file is sensitive

An unemployment file contains your NISS, your household composition, sometimes medical certificates for an exemption. This data falls under the GDPR, and medical certificates fall into the special category of health data.

Two precautions are enough, but they are non-negotiable:

1. Check the number digit by digit before pressing send. A fax that lands with a stranger is a data breach; our page fax sent to the wrong number sets out what to do if that happens.
2. Only fax a medical document the recipient actually needs, and prefer the doctor's or health insurance fund's channel where one exists. The topic is covered on fax and health data.

If you receive incoming faxes at home or in a small office, a cross-cut shredder stops draft social security documents from ending up intact in a bin bag.

Key takeaways

• ONEM decides, the payment institution (CAPAC or trade union) pays: identify the right one before you send.
• Control card, benefit claim and identification: never by fax, eC3 and the counter handle those.
• Fax remains useful for an urgent additional document, confirmed by an officer, sent to a specific office.
• A transmission report is freely admissible evidence under Belgian law: solid within a bundle, insufficient on its own for a procedural act.
• For an appeal, use the prescribed judicial route, not fax.
• Activate eBox: it removes the postal delay on decisions, which gives you that much more time to react.

For an overview of the Belgian institutions you can reach and best practice by recipient, see our page faxing an institution and the destinations – Belgium page.