eSIM, SIM only, ICCID: your mobile contract glossary

Twelve words turn up in every Belgian mobile contract pack, and four of them carry an amount. On the rate card I checked on 24 August 2026, misreading “SIM only” costs up to €720 over two years, and misreading “handset balance” costs €448.50 in one go.

The words of the contract, and exactly where each one is written

Between 2013 and 2020 I had these packs signed across a shop counter in Namur. Then I spent three years in the cancellations department of a Belgian virtual operator, reading them back over the phone to people who were discovering their content on the way out. Always the same twelve words, and always the same sentence in reply: “nobody explained that to me”.

Alphabetical order is useless here. What matters is where the word is written, because three distinct documents commit you on the same day: the tariff information sheet handed over before signing, the particular terms that describe your plan, and the general terms that describe everything else. A word that appears only in the third document is no less enforceable than the other two.

That table is the real table of contents of your contract. The rest is layout.

What does “SIM only” mean on a Belgian bill?

That the billed line covers the service, and nothing else.

No handset, no device instalment, no amortisation schedule in the annex. The plan comes down to a data allowance, calls, texts, a monthly price and a term. It is the only family of offers where cancelling triggers a single bill, the one for the service, so you can change your mind without owing anything on hardware.

The price gap between the two worlds is the first figure to keep in mind. On the rate card checked on 24 August 2026, the entry plan from DIGI Belgium is €9 a month for 60 GB with no term, so €216 of service over two years. The unlimited plans that handset offers most often attach to are €39 at BASE, €40 at Orange Belgium, €41.16 at Telenet and €49.99 at Proximus. Twenty-four months at €39 comes to €936: €720 more than the entry plan, for the service alone. The price applied from month thirteen is published by none of the four, and I am not going to estimate it on their behalf.

One piece of vocabulary trips up a lot of people: “SIM only” does not mean “no commitment”. A SIM-only plan can perfectly well be signed for twenty-four months. The two words live on two different lines of the particular terms, and you have to read both.

eSIM, ICCID, EID: three words for the same card

An eSIM is a chip soldered into the device, onto which the operator downloads a profile instead of handing you a piece of plastic. Orange Belgium and Proximus have offered it since 2020, Telenet since early 2024. On the contract side it changes strictly nothing: same plan, same term, same exit procedure, same handset balance if a device is financed alongside.

What it does change is the number you will be asked for on the way out. On a physical card it is the ICCID, nineteen or twenty digits printed very small on the plastic holder, starting with 89 then the country code. On an eSIM it is the EID, the identifier of the chip itself, read in the device settings. Neither one appears on your bill. People throw the plastic holder away on activation day, then spend half an hour on the phone eighteen months later trying to find the number again.

Photograph the card holder before you throw it out. That is all.

Does a virtual operator sign the same contract?

The same contract, yes. The same counterparty, no.

A virtual operator, or MVNO, sells subscriptions without owning any masts: it rents access to the network of an operator that does. The Belgian market has counted four networks since DIGI arrived, and a good ten brands running on them, among them Mobile Vikings, Scarlet, hey!, Jim Mobile, Lycamobile, Ortel Mobile and Youfone. The rate card checked on 24 August 2026 records, for instance, that Mobile Vikings runs on the Proximus network.

The distinction is contractual before it is technical. Your counterparty, the one who bills you, the one your cancellation must be addressed to and the one you will name before the ombudsman, is the brand written in the contract header. Not the owner of the masts. A Scarlet customer who writes to Proximus has cancelled nothing at all, and the notice period keeps running.

The rights are identical. Belgian electronic communications law applies in the same way to network operators and to virtual operators, and the BIPT says so without ambiguity. What varies from brand to brand are the channels: some have no shop, others no phone line, and that is paid for in time on the day something goes wrong.

“Unlimited” is read together with the reasonable-use clause

The word “unlimited” applies to the allowance, never to the speed.

The four unlimited plans on the rate card checked on 24 August 2026 all come with a reasonable-use clause, better known under its English name of fair use. Beyond a monthly threshold, the speed is reduced until the end of the month. You keep consuming, but slowly. None of the four recorded operators publishes that threshold, so the field stays “not published” in my tables: I am not going to invent a figure the contract does not give.

The same clause governs two other uses people assume are settled: tethering, which is deducted from the included allowance and sometimes capped separately, and roaming in the European Economic Area, where the allowance usable from abroad depends on the price of your plan rather than on its unlimited label.

What does a misread word cost?

Between €156 and €720, depending on the word and the moment.

I took the four terms that carry an amount and placed them on the contract timeline, with the figures from the rate card checked on 24 August 2026 and the standard amortisation schedule of a €599 device financed over twenty-four months.

The second row deserves a note, because it is more favourable than people think. The fee claimed for early termination of a fixed-term contract cannot exceed the subscriptions you would have paid until the end of the sixth month. Leaving at the end of month two on a €39 plan therefore means four monthly fees at most, so €156, and not the eighteen remaining months. Past the sixth month of performance, no fee at all is due on the service, and the contract says so because the law requires it.

That right applies in the same way in Wallonia, in Brussels and in Flanders: the matter is federal, and no regional rule alters it.

Termination fee and handset balance: two separate debts

This is the costliest confusion in the sector, and it fits in one sentence.

The termination fee covers the service and dies after six months of performance. The handset balance covers the device, never dies before its term, and stays capped at the residual value written in the amortisation schedule attached to the contract. Two debts, two regimes, one closing bill.

The six lines to have written down before signing

Ten minutes at the counter, and in writing: a spoken answer binds nobody.

• The exact name of the plan, and whether it is SIM only or attached to handset financing.
• The contract term in months, which is not the same as the length of the promotion.
• The price applied from month thirteen, when the introductory rate drops away.
• The termination fee for leaving in month three, worked out in front of you.
• The handset balance at month twelve, read from the amortisation schedule rather than estimated from memory.
• The ICCID or EID of your line, written somewhere you will find it again in two years.

If one of those six lines cannot be written down, it is not the salesperson's problem. It is that the contract does not say it clearly.

To compare plans on their twenty-four-month cost rather than on the introductory price, the comparison tool puts them side by side and the mobile plan ranking orders them on that total. On the contract term itself, the article on plans with or without a commitment sets out the six-month rule; on the handset balance, the 24-month credit behind the €1 phone gives the schedule month by month.

In a dispute over a bill or a closing statement, the Telecommunications Ombudsman Service handles the file free of charge, and the FPS Economy publishes the framework that applies to Belgian telecommunications contracts.

Sources

• BIPT, the Belgian telecommunications regulator, contract termination and the regime of the early termination fee, consulted on 3 September 2026.
• FPS Economy, telecom contracts and termination, consulted on 3 September 2026.
• Telecommunications Ombudsman Service, free handling of billing and termination disputes, consulted on 3 September 2026.
• Belgian operators' communications on eSIM support, recorded on 3 September 2026.
• Rate cards published by Belgian operators, recorded on 24 August 2026. Amortisation schedule built on a device with a €599 reference price, a €1 down payment and linear financing over 24 months.