Disputing a mobile bill: from operator to ombudsman

In writing, within your contract's deadline, paying only what you do not dispute. That is the method, on the operator's side. If it does not correct the bill, the Telecommunications Ombudsman Service takes over at no cost, and the operator must then freeze debt collection for up to four months.

In the cancellations department of a Belgian virtual operator, every week I saw customers who had "called three times". None of those calls counted. A dispute that does not exist in writing does not exist at all, and your contract's deadline keeps running while you wait on hold.

How long do you have to dispute?

Less than you think, and not the same deadline from one operator to the next.

There is no single legal deadline. The deadline is a clause in your general terms. The ones I recorded on 17 October 2026 give 30 days from the bill's issue at Proximus (version V.20210816), two months at Telenet and three months at Orange Belgium (postpaid terms of 15 October 2024). The clause-by-clause detail is in the article on reading your mobile bill line by line.

The fourteen days you often read appears in none of these three texts. It does you no harm either: disputing early has never lost anyone a case. The federal portal Droits Quotidiens points out that prolonged silence can be read as acceptance of the bill.

A second clock runs, a longer one: the ombudsman turns down a complaint lodged with the operator more than a year earlier.

How do you dispute a mobile bill, step by step?

Six steps. The first four happen with the operator, and they are what make the fifth possible.

1. Isolate the disputed line. Out-of-bundle use, roaming outside the zone, a premium-rate service, a handset instalment after the financing has ended, a monthly fee different from your specific terms. Note the exact amount, to the cent.
2. Find the clause. Your plan's price is in the specific terms, the dispute deadline in the general terms. You are disputing a gap between the bill and the contract, not an impression.
3. Write to the operator. Online form, email or letter. Registered post is not required, but it is the best proof once things get tense. Give the bill number, the line, the disputed amount and the reason.
4. Pay the undisputed part. And say so in the same message. The step is detailed just below.
5. Go to the ombudsman if the answer does not come or does not satisfy you. Online form, email or post, in French, Dutch, German or English.
6. Complete the file within ten days if the ombudsman asks you to. An incomplete file stays on hold, and the collection freeze only starts with a complete file.

Do you have to pay the disputed bill?

Only part of it: the part you do not dispute.

Paying everything means accepting everything. Paying nothing exposes you to a reminder, then a line suspension over the part nobody disputes. The middle road is the only one that holds, and Droits Quotidiens describes it the same way: settle the undisputed amount, dispute the rest in writing.

Take my standard case: a €39 monthly plan, 24-month commitment, post-promotion price not published, site rate card recorded on 24 August 2026, with a €599 device financed at €24.92 a month. A bill arrives with €61.50 of data used outside the zone, although the line was blocked for use abroad.

In writing, one sentence is enough: "Today I am paying €63.92, corresponding to the monthly fee and the handset instalment, and I dispute the €61.50 out-of-zone data line for the following reason." The transfer carries the same reference as the bill.

Your direct debit has already been taken: what now?

Ask the bank for a refund, then write to the operator the same day. In that order, or close to it.

European SEPA direct debit rules allow eight weeks to recover an authorised debit, without having to justify it to the bank. The refund settles nothing with the operator, which will simply see an unpaid bill. Hence the written dispute, sent at the same time, together with payment of the undisputed part. Without that message, you get a reminder. The first one is free of charge, the following ones cost €10 each at most according to the BIPT.

What does the ombudsman do, and how long does it take?

It freezes, it conciliates, then it recommends.

The procedural rules of the Telecommunications Ombudsman Service set every deadline. I lined them up on a bill issued on 3 November, with each operator's dispute deadline as recorded on 17 October 2026.

The freeze ends after four months, or sooner if the mediation succeeds. If the operator does not follow a recommendation and lets the reply deadlines pass, it commits to applying it for your personal compensation. Nothing changes from one region to another: the matter is federal, and the procedure is the same in Namur, Brussels or Ghent.

One dispute in four is about the bill

The ombudsman received 15,087 written requests for intervention in 2025, according to its annual report published in March 2026. Billing accounts for 28.63%, the leading cause of complaint ahead of service outages. The remedy is nothing exceptional: billing is the busiest queue in the service.

The documents to attach to the file

The ombudsman works on documents. Send them all at once:

• the disputed bill, with the line highlighted;
• your specific terms, where the price and the commitment period appear;
• your written dispute to the operator, dated, and proof of sending;
• the operator's answer, or a note that it did not answer;
• proof of payment of the undisputed part;
• any useful technical evidence: a screenshot of the roaming block, a usage statement, an alert text received or not.

A complete file on day one means a collection freeze that starts on day one.

Sources

• Telecommunications Ombudsman Service, procedural rules, articles 6, 8, 9, 10, 13, 14 and 20, consulted on 23 October 2026.
• Telecommunications Ombudsman Service, announcement of the 2025 annual report, 25 March 2026; billing share (28.63%) taken from L'Avenir, 26 March 2026.
• Droits Quotidiens, "Comment contester ma facture de téléphonie ?" and "J'ai déposé plainte au médiateur télécom, dois-je quand même payer ma facture ?", updated on 12 March 2026, consulted on 23 October 2026.
• BIPT, "Unpaid bill", consulted on 17 October 2026.
• General terms of Proximus (V.20210816), Orange Belgium (postpaid, 15 October 2024) and Telenet (undated version), dispute clauses read on 17 October 2026.
• Site rate card recorded on 24 August 2026; €599 device, €1 down payment, €598 financed linearly over 24 months. The price applied after the promotional period is not published and has not been estimated.