Unlimited mobile data: where does the contract stop?

No, unlimited data is not unlimited. In Belgium, the word stands for a precise threshold: 300 GB a month at full speed, then reduced speed until the next cycle. The figure does not come from the operators but from the regulator, and it changes size as soon as you cross a European border.

The word "unlimited" is a 300 GB threshold

The BIPT published on 23 February 2022 guidelines on unlimited browsing. An operator may only use the word if the volume lets the great majority of customers browse with no speed limit. The bar is set at 300 GB a month for mobile and 3 TB for fixed internet. Operators had six months to comply.

The text also says how to handle the threshold. Blocking access or automatically charging a surcharge is "not recommended". An automatic speed reduction is. And the overrun rule must be written clearly before signing, in the contract and on the website.

It is a guideline. Not a law.

The nuance matters on the day of a dispute: you will not quote an article of the Code, you will quote the regulator. In practice, the whole market has fallen into line, and I found no plan sold as "unlimited" below this threshold in the 28 October 2026 survey.

Why did the BIPT set the bar at 300 GB?

Because, in 2022, more than 10% of customers on most mobile products went over the threshold of their fair use policy, against less than 2% on fixed internet. The word was therefore misleading for one customer in ten. The press release says the limits will be reviewed as usage grows: nothing has moved since.

Seven so-called unlimited plans, recorded on 28 October 2026

They all stop at the same place. The differences lie in the speed that remains, the volume you take to Europe and the way the price changes.

Prices with no promotion displayed are list prices: no switch in the thirteenth month is published for them. Proximus is the only one to show its own, a €15 discount for twelve months on an online subscription before 1 November 2026. Over 24 months, that comes to €1,019.76 at Proximus, €960 at Orange Belgium, €984 at Telenet and €576 at hey!.

Origin of each line: Proximus Mobile Unlimited page and Telenet "Mobile residential" information sheet (undated), read on 28 October 2026; Orange Mobile Unlimited legal notice (December 2025 document, at €39) and the increase to €40 on 18 January 2026 recorded by Test-Achats; hey! terms in force since 18 October 2026 and BASE price taken from Selectra (October 2026); Mobile Vikings prices taken from Test-Achats (21 August 2025). The boxes I could not read at the operator stay "not published".

In Europe, how much of the unlimited is left?

Between 36 and 75 GB guaranteed, depending on the plan's price. More only if the operator chooses to give more.

The "roam like at home" principle, extended until 30 June 2032 by Regulation (EU) 2022/612, has an exception for open data bundles. The operator may apply a fair use limit when roaming, provided it reaches at least twice the monthly price excluding VAT divided by the European wholesale cap. That cap is €1.10 per GB in 2026 and drops to €1.00 on 1 January 2027. The European Commission's Your Europe page sets out the calculation and the obligation to tell you this volume.

I ran the calculation for each plan, with Belgium's 21% VAT removed.

Two readings. The first is reassuring: Proximus and Telenet give in Europe the same allowance as in Belgium, four to five times the minimum. The second is less so. At Orange Belgium, the legal notice states that browsing in Europe is "deducted from the plan" and that once the included volume is used up, speed drops to 512 kbps, without ever putting a figure on that volume. The legal minimum for €40 is 60.1 GB. Beyond a plan's European volume, the surcharge cannot exceed the wholesale cap, that is €1.331 per GB including VAT in 2026.

Note the effect of the promotion at Proximus: the European floor follows the price. During the twelve months at €34.99, it is 52.6 GB; it rises to 75.1 GB when the price moves to €49.99. Proximus does not use this, since it writes 300 GB. An operator sticking to the minimum could.

The objection: nobody reaches 300 GB

It is a fair one, and I take it seriously.

The BIPT measured average usage of 11.9 GB a month in 2025. The 300 GB threshold is twenty-five times higher. For normal use in Belgium, unlimited is unlimited in practice, and the break-even calculation in the article on how many GB per month for your usage shows that it costs a lot for what you use.

But a customer paying €40 instead of €15 is not buying Belgian gigabytes he will never use. He is buying three things. Peace of mind that no out-of-bundle bill will ever arrive. The option of working on a laptop through tethering. And holidays without counting. Each of these three uses has its own clause, and that is where the word lies. At the counter in Namur, the customer who came back unhappy with an unlimited plan had almost never used it up in Belgium; he was back from Spain with his speed throttled on the tenth day, or he had put the SIM in a router at home.

Is tethering included in unlimited?

Yes, in the same allowance. Making the line available to others is the problem, not tethering.

Proximus writes on its Mobile Unlimited page that the smartphone can be used as a hotspot, without setting a separate limit. Telenet goes further by offering a Data SIM Unlimited at no extra cost, with 300 GB per data card, to connect a laptop or tablet without going through the phone. Selectra noted on 10 August 2026 that no Belgian operator forbids tethering.

The limit lies elsewhere. The Orange Mobile Unlimited legal notice classes "making available to third parties" of the SIM card as abusive. An unlimited SIM slipped into a 4G router to provide internet for a whole household can fall under this clause, even without going over 300 GB. In principle, the operator is the judge, and that is exactly what you want to avoid. A household needs a fixed broadband subscription or a 4G box, not a diverted mobile line.

Unlimited calls have a ceiling too

People forget, because nobody comes close. The Orange Mobile Unlimited legal notice presumes that normal use does not exceed 10,000 minutes and 10,000 texts a month. Also targeted are more than 250 different contacts in the month, uninterrupted calls of more than three hours, SIM boxes, call centres and machine-to-machine connections. The sanction ranges from restriction to termination. Telenet, for its part, refers to "normaal gebruik" described in its special conditions, which the information sheet does not reproduce.

Ten thousand minutes is more than five and a half hours of calls a day, every day. The ceiling is not aimed at the chatterbox. It is aimed at resale.

Which clauses should you read before signing an unlimited plan?

Five lines, all in the plan's legal notice or information sheet, never on the poster:

• the threshold, in figures, beyond which speed drops, and the exact speed that remains (512 kbps or 1 Mbps, the difference doubles loading time);
• the volume usable in the European Union, written in gigabytes, and the rate beyond it;
• the date on which the promotional price ends, since the European floor follows it;
• the abusive use clause: making available to third parties, router, machine-to-machine connections;
• the tethering rule, or the existence of an associated data card.

If one is missing, ask for it in writing and keep the answer. A "no figure" box is settled before you leave, not when you come back.

The rule is federal: nothing changes between Wallonia, Brussels and Flanders. To compare plans on their 24-month cost rather than on the word on the poster, the mobile plan ranking and the comparison tool set them side by side. And if the Belgian allowance does run short, top-up rates are in the article on extra mobile data.

Sources

• BIPT, press release "Plus de clarté sur le surf illimité" (more clarity on unlimited browsing), 23 February 2022: thresholds of 300 GB and 3 TB, speed reduction recommended, information obligation.
• BIPT, publication on mobile data usage in Belgium (11.9 GB a month in 2025).
• Regulation (EU) 2022/612 on roaming, wholesale data caps; European Commission, Your Europe page on roaming, consulted on 28 October 2026.
• Proximus, Mobile Unlimited page: €34.99 for 12 months then €49.99, no commitment, 300 GB in Belgium and the EU zone, 512 kbps beyond, hotspot allowed, consulted on 28 October 2026.
• Orange Belgium, Orange Mobile Unlimited legal notice (December 2025 document, undated): 300 GB then 512 kbps, EU browsing deducted from the plan, normal and abusive use, read on 28 October 2026.
• Telenet, "Mobile residential" information sheet, undated: Mobile Unlimited at €41, 300 GB then 1 Mbps, same conditions in the EU zone, Data SIM Unlimited, read on 28 October 2026.
• Test-Achats, Orange price increase of 18 January 2026 (article of 19 November 2025); launch of the Mobile Vikings Unlimited plans (21 August 2025).
• Selectra Belgium: hey! Mobile Unlimited since 18 October 2026 (€24, 300 GB, 1 Mbps, 60 GB in the EU); tethering (10 August 2026); BASE 300 GB plan at €39 (October 2026).
• Commitments and post-promotion prices not published by the operator: not estimated.