Enough is enough! Is your latest electricity and/or gas bill huge? Rest assured: there could be several explanations for an unusually high amount and you can sort it out!


Your contract has just been renewed and you notice an increase in the amount of your payment invoices? You have just switched supplier to save money and yet your payments are higher? You want to adapt or change your payment invoices but you don’t know how? You have received an exorbitant adjustment invoice? Here are a few keys to getting a better picture of your interim and annual bills.

What is a payment invoice?

It is a partial payment of an amount payable. In the electricity and gas sector, you can choose the frequency of these payments. Usually, consumers pay monthly instalments but you can sometimes choose bimonthly (every two months) or quarterly (every three months) instalments depending on the electricity and gas supplier you choose thanks to the energy comparison website.

How are my instalments calculated?

The instalments are usually calculated on the basis of the records of your consumption. This is known thanks to your energy meter reading and then communicated to your supplier by the distribution system operator (DSO) active in your town.  But if you have changed supplier or have moved into a house that has just been connected to the electricity and/or gas grid, no consumption records are available.

The supplier will then base itself on the consumption you will have provided when registering or on the size of the dwelling, your energy usage and the number of people in the household. Then the supplier will estimate your annual electricity and/or gas bill on the basis of this consumption and will calculate the amount of your instalment.

The payment invoices are based on your consumption of the previous year.

Calculator with coins

The payment invoices are based on your consumption of the previous year.

If it is very cold, will my interim bills increase?

Seasonal temperatures are also taken into account to estimate your payments. However, after a particularly harsh winter when you have consumed more electricity and/or gas, the supplier will not necessarily increase payments the following year.

NB: as the calculation method can sometimes vary from one provider to another, your payment invoices may be slightly higher after switching provider, even if your consumption remains the same. For further information, please contact one of our staff on 0800 37 456.

How do I calculate my annual settlement bill?

For your annual settlement bill, your distribution system operator will perform a meter reading, which it will then forward to your supplier.  With these figures, the provider can determine your exact consumption of electricity and/or gas in the year and will tell you if an amount must be refunded (you consumed less than forecast), or if there is a balance owed (you consumed more than forecast). This is called adjustment.

Is my payment invoice identical regardless of the season?

The amount of your payments will always be fixed throughout the year, regardless of the contract length selected and its features.  Thus, even for a contract with a variable rate, you will pay the same amount every month.

Why have my payments increased?

This usually occurs in two cases:

  1. If you are at the end of your energy contract, when it is automatically renewed, a new rate card will be applied. These new rates will often affect your new instalments as well as your final settlement. Each year, therefore, it is important to compare the price of electricity and gas to be sure to enjoy the best energy rates on the market.
  2. In your gas or electricity bill, certain amounts are independent of the supplier. Notably the costs of distribution and transmission that can change every year. These costs must be passed on to your payment invoice by the supplier, even if it is not linked to your rate plan! This explains why your payments may increase.

Also, if you changed your billing frequency, the amount shown on your invoice will also have changed. Indeed, paying every month or every three months does not require paying the same amount in one go.

How do I change my instalments in case of under or over estimation?

Although payments aim to be the as accurate a representation of your consumption as possible, you may wish to anticipate some changes (one person less or more in the household, the installation of photovoltaic panels, insulating your house, the purchase of energy-saving devices…). It is therefore quite possible to ask the supplier to adapt your instalments. The frequency of payments can also be changed with most suppliers (monthly, bimonthly, quarterly).

In general, a simple phone call to the supplier will allow you to change your payments. But you can also make the necessary changes online. We have listed below, for each supplier, the easiest way to change the instalment amount.

If, however, after reassessing your instalment payments, you consider you pay too much, then maybe it’s time to compare prices of electricity and gas in order to choose a more competitive supplier.

How can I ask my supplier to adjust the amount of my monthly payments?

Engie Electrabel




  • Service ENECO: 0800/17.451




  • Customer service: 0800/291. 91



Can a mistake account for a high gas or electric bill?

Red crossIf after checking it the unusual amount of your invoice cannot be explained by a change in your habits or equipment, or by an increase in the cost of gas or electricity, then it may be the result of a reading error. To find out if this is the case or not, check the index set out in your settlement bill. It is wrong? Make a claim with your provider asking it to rectify it in order to receive a correct invoice this time. However, be sure to pay the amount that you are not contesting in proof of your good faith and prevent being cut off.

Moreover, sometimes information can be distorted because of a defective meter. Note: following a meter change, the consumption indicated may sometimes seem excessive. But this actually highlights how the old one didn’t work properly. If you are still considering this possibility, you can put your queries to your DSO. It will then install a control meter which will work in parallel with your current one. Note that you will be charged for this but you will be refunded if a problem is detected.

Finally, when you notice a major increase in consumption for no apparent reason, make sure you have not fallen victim of electricity theft. Another consumer might indeed be wired up to your meter.