TTF gas price: the quote you are reading does not index your Belgian bill

You type "TTF gas price", a number appears, say 81 €/MWh. And then what? That number looks nothing like your bill, where gas is counted in cents per kilowatt hour. Worse: in Belgium, the quote you have just read is probably not the one indexing your contract. Here is how to move from one to the other, and why the gap between them is entirely normal.

TTF, ZTP, Belpex: three indices, only one indexes your gas

TTF, short for Title Transfer Facility, is the virtual gas trading point of the Dutch zone. It is Europe's largest gas marketplace, the one financial wires and live price widgets quote. When a newspaper headlines "the price of gas in Europe", nine times out of ten it means TTF.

ZTP, short for Zeebrugge Trading Point, is the Belgian and Luxembourg hub. Much smaller volumes, but anchored to the Belgian physical market.

Belpex does not belong in this list at all: it is the Belgian power exchange, not a gas one. The confusion is common because all three acronyms live side by side in the same tariff conditions.

Since 1 October 2023, Fluxys has merged its two trading services, ZTP Physical and ZTP Notional, to publish a single Belgian reference price: the ZTP Trading Service. The Belgian market therefore has one index, and most residential offers have attached to it.

How much is a quote of 80 €/MWh on your bill?

8 cents per kWh. Nothing more complicated.

A megawatt hour holds one thousand kilowatt hours. A quote expressed in euros per MWh therefore converts into cents per kWh by dividing by ten. The rule fits on one line and nobody spells it out: 1 €/MWh equals 0.1 c€/kWh.

The right hand column is the only one that speaks. It assumes the Belgian household reference consumption of 17,000 kWh of gas per year, and counts the raw material alone. No margin, no network, no excise, no VAT.

If you think in cubic metres, the bridge is the calorific value: the 82.55 €/MWh of 14 September 2026 corresponded to 0.9576 €/m³, which implies a conversion coefficient close to 11.6 kWh/m³. Our guide on converting gas m³ into kWh explains why that coefficient varies with your municipality.

How far below TTF does ZTP trade?

Over the available history, the Belgian index has settled on average around 14 % below Dutch TTF, with episodes where the gap was measured in tens of euros per MWh. ZTP, closer to the Belgian physical market and less liquid, absorbs international shocks less brutally than its large neighbour.

The practical consequence is rarely stated: estimating a Belgian bill from the TTF quote means overestimating it. On a quote at 81 €/MWh, fourteen percent is nearly 11.5 €/MWh, that is 1.15 cent per kWh, that is roughly 196 € a year on 17,000 kWh. The order of magnitude is not trivial.

The gap is not guaranteed in that direction at every instant. It flips occasionally when Belgium faces a physical constraint the Netherlands does not. But the long run average leans the Belgian way.

TTF tells the story of Europe. ZTP tells the story of Belgium. Your Belgian bill listens to the second one.

Why does today's quote never reach today's bill?

Because the indexation parameter is a backward looking average, not a live price.

The definitions published by CREG, the Belgian federal energy regulator, are explicit. A parameter of the 101 type uses the arithmetic average of closing quotes of the month preceding the supply month. A 103 type uses the average of the month preceding the supply quarter. Put plainly, you always pay the past.

Take the real case of September 2026. The surge seen around 10 September, with TTF futures above 81 €/MWh, a level unseen since late 2022, has strictly no effect on a September bill. On a monthly contract it arrives in October. On a quarterly contract indexed on 1 January, it waits four months before existing for you.

ZTP101, ZTPRLP, TTF103: decoding the parameter written in your contract

These codes are not decorative jargon. On their own they determine how reactive your price is.

The hundreds digit says what product is quoted, the tens and units say the averaging window. The RLP tag stands for the residential load profile: the average is then weighted by the typical offtake curve of a household, which obviously burns more in January than in July.

Beyond the parameter itself, five elements of the formula weigh as much as the index and escape the market entirely:

• the mark up, a fixed amount added to the parameter, in c€/kWh;
• the multiplier coefficient applied to the parameter, sometimes above 1;
• the annual subscription fee, independent of your consumption;
• the commercial margin folded into the coefficient, which nothing obliges anyone to publish separately;
• the revision frequency, monthly or quarterly, which decides the lag.

Two contracts tied to the same ZTP101 can therefore produce very different bills. The parameter is identical; everything else is not. Our comparison of fixed, variable and dynamic energy contracts sets out what each formula means day to day.

From quote to amount paid: the stacked layers

The molecule is only the first layer. Here is the full stack, for a Walloon household using 17,000 kWh a year, with mid September 2026 values.

Only one of those five lines depends on the world market. Only one depends on your supplier. The other three are identical for everyone in a given municipality.

That is why a quote that doubles never doubles your bill, and why a quote that collapses never erases it. We detailed that mechanism in our analysis of gas prices in Belgium in 2026, where the fall in wholesale markets gets absorbed on the way by excise duties and network charges.

The gap between September's quote and July's price lists explains itself

One disconcerting figure deserves to be put plainly. In July 2026, Walloon price lists showed an energy component between 4.44 and 7.47 c€/kWh. On 14 September 2026, the raw ZTP quote was worth 8.26 c€/kWh. The market therefore cost more than suppliers were charging two months earlier, margin included.

There is no anomaly in that. July's price lists reflected June quotes, in a market that was still relaxed. Over twelve months, the ZTP monthly average moved from roughly 0.3659 €/m³ in October 2025 to 0.8793 €/m³ in September 2026, a rise of 140 %. Translated into euros per megawatt hour, that is a jump from about 31.5 to 75.8 €/MWh.

Autumn price lists will carry that increase. They had not carried it in July, quite simply because the indexation parameter looks behind itself.

Should a household follow the live gas price?

No, unless the contract is dynamic.

A fixed contract makes the quote entirely irrelevant to you until maturity. A variable one follows it a month or a quarter late, and no household has any way to act on that lag. Only a dynamic contract, where the price tracks the quote day by day, justifies watching the market, and even then: on gas, unlike electricity, there is almost no room to shift consumption in time. Heating comes on when it gets cold.

The genuine use of the quote, for a household, comes down to two moments.

Choosing between fixed and variable when signing, first. A historically high quote makes locking a fixed price less attractive, a low one makes it more interesting.

Understanding a change in the bill, second. When the advance payment climbs, knowing whether the quote has moved separates a market increase from an estimating error. Our guide on lowering your energy advance payments treats that check as the first reflex.

Wallonia, Brussels, Flanders: the quote is national, the rest is not

ZTP is a single point for the whole of Belgium. Whether you live in Arlon, Antwerp or Ixelles, the molecule is worth the same at the same instant. What changes is everything stacked on top.

The federal regulator, CREG, remains competent for quotations, excise duties and wholesale market supervision. A DSO, or distribution system operator, is the company that owns the pipes in your street: you never choose it, and it is not your supplier. Regional regulators handle distribution and public service obligations. If your dispute is about the price per kWh, it is federal; if it is about network tariffs or connection, it is regional.

Key takeaways

Divide by ten to move from euros per MWh to cents per kWh, check in your tariff conditions whether your parameter starts with ZTP or TTF, and look at its revision frequency: monthly means you follow the market one month late, quarterly means up to four. Every figure quoted here dates from mid September 2026 and variable offers are reindexed every month, so check them again before signing. The gap between contracts remains by far the most effective lever: our energy supplier ranking prices it for real consumption, gas and electricity together.

Sources. CREG, official gas and electricity quotations page and definitions of the indexation parameters (TTF101, TTF103, ZTP101). Fluxys, merger of the ZTP Physical and ZTP Notional services on 1 October 2023 and operation of the ZTP Trading Service. FEBEG, documentation on the indexation of variable price contracts. CWaPE, Brugel and VREG for 2026 distribution tariffs. Quotation readings of 10 and 14 September 2026 and ZTP monthly averages from October 2025 to September 2026. Pages consulted on 18 September 2026. Variable offers are reindexed every month: check the price list in force before signing.