Getting the best from your gas or electricity supplier

You need to make sure you are getting a good deal from your gas and electricity supplier, whether or not you are considering staying with them or switching …

Do I need to take regular meter readings? 

Taking regular meter readings is one of the best ways to stay on top of how much energy you are using. If you don’t submit meter readings to your supplier they may send you bills based on estimates and these can be inaccurate. If your bill has been overestimated then you are paying for fuel you haven’t actually used; if it’s been underestimated then you won’t be paying enough and may face a large debt when the meter is eventually read.

Some suppliers may offer you a smart meter, which automatically sends meter readings to your supplier. If you already have a smart meter and then switch, you may lose this functionality, meaning you’ll have to take meter readings manually again.

Is it cheaper to buy both electricity and gas from the same supplier?

Often, but not always. Buying both fuels from the same supplier is convenient but may not be the cheapest option. Many suppliers no longer offer a Dual Fuel Discount. If you have one supplier for gas and a different one for electricity then you can check with both to see which would offer you the better deal to become a dual fuel customer. However, to find the cheapest available tariff it’s better to use an independent comparison service and check tariffs from separate suppliers as well as dual fuel options.

What is a fixed rate tariff?

Unless you have requested otherwise, you will be on the variable (usually called Standard) tariff with your energy supplier. This is often the most expensive tariff, and also means you will be affected by any price changes your supplier implements.

Fixed-rate tariffs tend to be cheaper than variable tariffs. A fixed-rate tariff means the price you pay for each kilowatt hour (kWh) unit of gas or electricity you use, and for your daily standing charge, will stay the same for the duration of your contract (which usually lasts for one or two years). How much you pay each month will still be affected by how much energy you use.

If your supplier drops its prices after you’ve started your fixed rate contract you might end up paying more than the variable tariff. However, in recent years the trend has been for energy prices to go up rather than down, although the government has set a price cap

Your energy bill or statement must now show whether there is a cheaper tariff your supplier can offer you.

However it is usually better to contact your supplier directly to check. If you are on a variable tariff this section of the bill may not show fixed tariffs, or it might only list a direct debit or online option, which may not suit you.

You can leave a fixed rate contract any time you like. In some cases you can leave for free, but you’ll usually have to pay an exit fee. When your contract ends, either move onto the next cheapest tariff (otherwise you will put on the more expensive variable tariff), or consider switching.

Is it cheaper to pay by direct debit?

Usually, yes. Energy suppliers can no longer offer ‘discounts’ to direct debit customers, but as they can still restrict access to the most competitive tariffs to those prepared to pay by direct debit, it amounts to a discount in all but name. The other advantage to paying by direct debit is that it spreads the cost of fuel evenly over the course of the year, avoiding high winter bills.

Direct debit payments are based on estimates of how much energy you will use, which may be over or under estimated. Your supplier is only obliged to attempt to read your meter once every two years so, to avoid shock bills, submit a meter reading every time you receive a statement. Your direct debit should be reviewed at least once a year to make sure you’re not paying too much and building up credit, or too little and building up debt.

What if I prefer pre-payment? 

Prepayment meters work on a pay-as-you-go basis. You top up a key or a card at a pay-point and then stick it in the meter, which tops up your available credit. Some people like prepayment meters because they help with budgeting and they do not allow you to build up a big debt (emergency credit is usually limited to £5). However, credit can run out at inconvenient times or you may find it difficult to get to a pay point. In this instance you might consider a smart pre-payment meter, which offers top-up methods by text or online, and a range of other advantages over standard pre-payment meters.

Some suppliers offer more than one pre-payment meter tariff, so you should still check if you are on the best deal.* Also consider switching supplier, as there may be a cheaper tariff elsewhere.

If you did want to start paying by direct debit, you would need to speak to your supplier about switching to a credit meter. This is easier if you have a smart meter, otherwise you may have to pass a credit check, or may be charged to change the meter.

* See our factsheets on prepayment meters and Smart Pay-As-You-Go meters.

Is an online tariff cheaper?

On average, an online tariff can save you a further 10% on your bills. Some suppliers offer competitive tariffs ut only if you manage your account online. Others may offer paperless billing discounts, where you receive your bills and correspondence by email rather than post.

Switching to a new supplier

Thinking about switching? According to the energy industry regulator, Ofgem, switching could save you around £300 a year. And despite what you might have heard switching gas or electricity supplier is very easy.

To find out what you could save, use one of the Ofgem-accredited independent comparison services listed below. You can do this online or over the phone. All of them offer accurate and impartial information about tariffs.  |  0800 074 0745  |  0808 1783 492  |  0845 345 5708  |  0845 330 7247  |  0800 011 1395  |  0800 849 7077  |  0203 468 0461  |  0871 711 7771  |  0800 862 0021 | online only | online only

Citizens Advice also offers a free, impartial online energy comparison service.

What information will I need?

Recent changes have made switching energy suppliers much simpler. One of these changes has been to ensure the bills you receive contain all the information you need to accurately compare energy suppliers. This can usually be found underneath the section called “about your tariff” (or something similar), which tells you:

  • The name of the tariff you’re on.
  • Method used to pay for your energy.
  • If you have to pay any fees to exit your tariff.
  • How much energy you use per year in kilowatt hours (kWh).

If you are on Economy 7 your comparison will be more accurate if you can separate out your annual day and night usage. Ask your supplier if this is not shown on your bill.

How much will I save? 

If your fixed tariff ends within the next year, comparison sites assume you will then move onto the more expensive variable tariff. Savings figures are based on this future prediction, although some sites allow you to compare savings against your spend from the previous year.

If you need to pay an exit fee factor this into any savings listed. Also bear in mind that if you owe your supplier money you will need to pay this when you switch.

If you receive the Warm Home Discount be aware that not all suppliers offer the discount. Also, unless you receive Guaranteed Pension Credit, if you switch before you receive the discount you will lose it that year.

Warm Home Discount

If your energy supplier has 250,000 customers or more, then they’re obliged to offer the Warm Home Discount. This is a rebate on the household electricity bill, which for the last few winters has been £140. It is automatically available to customers who receive the guarantee credit element of Pension Credit.

Suppliers also offer this discount to a broader group of customers, with each supplier having its own specific eligibility criteria. So if you receive any type of benefit or are on a low income it’s worth calling your supplier to check and apply. See

What’s the process of switching?

Once you’ve agreed a deal with your new supplier you’ll sign a new contract with them. They will then let your old supplier know you are leaving. The process of moving can take up to 21 days, but your new supplier should manage the process so contact them if you experience problems. You should to be told the date of the switch, and on this day take a meter read and submit it to your new supplier. Your old supplier will then send you a final bill to pay, and any direct debits should be cancelled.

Once you’ve switched, your old supplier is not obliged to reimburse you any credit left behind on your old account unless you specifically ask for it. You can claim credit back from an old account no matter how long ago it was. If you think your old supplier owes you some money back following a switch, visit

What if I change my mind?

By law you have a 14-day “cooling off” period to change your mind without incurring a penalty, starting from the day you take on a contract with a new supplier.

The switching process …

  1. Compare Tariffs
  2. Select tariff and notify new supplier
  3. The 14-day cooling off period
  4. New supplier takes up to 3 weeks to complete the switch
  5. Take meter reading on date of switch 

Am I allowed to switch if I’m renting?

If you live in a rental property and your name is on the bill, you have the right to switch to the energy supplier of your choice even if your tenancy agreement says otherwise. You also have the right to change your meter from a prepayment to a credit meter (or vice versa), although you may be obliged to change it back at the end of your tenancy.

The exceptions to this are if your landlord’s name is on the bill. If your landlord or lettings agency is unreasonably preventing you from switching you can contact Citizens Advice for guidance.

Reference numbers

Every gas and electricity supply has a unique reference number and you may be asked for this when switching.  They are unique to your house and won’t change if you change supplier.

The gas reference is called the Meter Point Reference Number (MPRN) and for electricity it’s called the Meter Point Administration Number (MPAN).

These are not the same as your customer account number or your meter serial number (printed on your meter). If you need to find them they should be located somewhere on your bill or statement.

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