FTTH, FTTB, FTTC: where does fibre really stop?

FTTH, FTTB and FTTC name the point where the optical fibre stops: at the home, at the building or at the street cabinet. Only the first one goes all the way to you. The rest of the route runs over copper or coaxial, and that last stretch sets the ceiling on your speed. Here is what each acronym covers, what Belgian plans make of them, and how to tell which one you are on.

FTTH, FTTB, FTTC: where exactly does the fibre stop?

The three acronyms read the same way: Fiber To The something. The last word marks the end of the glass.

For FTTH, Fiber to the Home, the fibre enters your home. For FTTB, Fiber to the Building, it stops inside the building. For FTTC, Fiber to the Curb, it stops at the kerb, in a street cabinet. Beyond that point another medium takes over, and it is slower. Wikipedia gives the same definitions.

Three acronyms, three last stretches

The last stretch explains almost everything. Fibre can carry far more than copper accepts, so as soon as a copper section appears, it is the one in charge.

Is FTTB real fibre?

It uses fibre, but not all the way to your home. The distinction matters.

The FTTH Council Europe, the association that brings together the European players in the sector, describes FTTB as a distribution point inside the building whose "final leg uses copper wiring". It adds that this set-up cannot be upgraded to higher data rates because of that copper, whereas FTTP, the other name for FTTH, offers "the highest possible data rates" (FTTH Council Europe, post on FTTB and FTTP). The same post speaks of "full-fibre" for FTTP, which in effect files FTTB under partial.

I found no Belgian residential plan that publicly sells itself as FTTB. In Belgium the acronym remains mostly an engineer's term, which is good news for readers: if your operator does not use it, you will only meet it in practice in an older building whose internal wiring was never redone.

FTTC: fibre at the kerb, copper all the way to you

This is the technology behind VDSL, which I compare with fibre in a separate article: fibre or VDSL in Belgium.

Fibre feeds a cabinet on the pavement. From there your old copper telephone line covers the last tens or hundreds of metres. The further the cabinet is from your home, the more the speed drops, which is not the case with FTTH. Proximus introduced vectoring in 2013, which pushed speeds up to 100 Mbps, then an "ultra-dense vectoring" announced with Nokia in May 2021, meant to double copper speeds where fibre is not planned in the short term (Telecompaper, 12 May 2021).

FTTC is therefore not bad. It is capped, and the cap is physical.

And coaxial cable, where does it fit?

Outside this family, but it earns a place here because its name causes confusion.

The Telenet and VOO cable networks also carry fibre to neighbourhood nodes, then switch to coaxial for the last metres. On paper it is a cousin of FTTB or FTTC. In practice it behaves differently: high download speed, shared between neighbours, and low upload speed. Proximus makes the point itself, since its fibre page claims that competitors use "coaxial on the last stretch", which would limit speed and stability (Proximus fibre page, checked on 10 October 2026). Bear in mind that this is a competing operator's argument: the figures below settle it better.

The full comparison is in FTTH fibre or coaxial cable in Belgium.

Speeds actually sold in Belgium: the table of 10 October 2026

Here is what each technology sells today, with a calculation the commercial pages leave out: upload as a share of download.

Sources: Proximus fibre page and the callmepower.be comparison, consulted on 10 October 2026. The percentages are my own calculation. These are advertised maximum speeds, not field measurements. BIPT, the Belgian telecom regulator (IBPT in French), calls them a "theoretical maximum speed".

The figure that stands out is not the download. It is the 4%. A cable subscriber on 2.5 Gbps receives fast and sends slowly, which matters for video calls, cloud storage and backups. Our analysis of fibre upload speed covers this point in detail.

How do you tell which technology you are on at home?

Three clues, in this order, before you even phone anyone.

• The technician fitted an optical box (ONT) fed by a thin fibre cable: it is almost certainly FTTH. The exact role of that box is described in what the ONT box does.
• Your modem plugs into a telephone socket: FTTC or FTTB.
• Your modem plugs into the coaxial TV socket: cable.

Then check the address. Depending on where you live, the wholesale network may belong to Proximus, to Fiberklaar in Flanders, to Wyre, or, according to Proximus, to Unifiber in Wallonia and GOfiber in the German-speaking community. Two neighbours on the same street may not have the same operators. The eligibility check is explained in checking fibre availability at your address.

Three regions, three realities

FTTH coverage is around 78% of homes in Brussels, 71% in Flanders and 44% in Wallonia as of mid-2026 (moving figures, check the BIPT atlas). The rest of the country depends on cable and VDSL.

In practice, a Brussels resident in an older building more often meets internal copper wiring, so an FTTB in effect. A Fleming in a recent housing estate is more often served by full FTTH. A Walloon outside the covered areas still chooses between VDSL and cable, depending on the municipality.

The mistakes that cost you speed

• Believing that a "fibre" plan is necessarily FTTH, when the word also covers mixed solutions.
• Comparing download speed alone and forgetting upload.
• Buying a 2 Gbps plan in a building whose internal wiring caps at 1 Gbps.
• Assuming the neighbour across the street has the same technology or the same operator as you.