Prepayment Meter Guide: PAYG Energy Explained

Illustration of prepayment energy meter cards

Using a prepayment meter can be a good option for those who prefer to know ahead of time what they are spending on their energy costs. Read on to find out how prepayment meters work, their pros and cons, how and where to top up and how to switch from a prepayment meter to a credit meter.

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What is a Prepayment Meter?

Prepayment meters are increasingly common with over four million households using them. This special type of energy meter requires the user to pay for their gas and electricity in advance, by topping up a card or key with credit at a Post Office, PayPoint or PayZone.

A prepayment meter can be an option for those who prefer to keep on top of their energy costs by budgeting ahead of time. Similar to a pay-as-you-go mobile, the cost of energy is deducted from your credit as you use it. However, if you use up your balance, your power can be temporarily cut off until you top-up again, unless you have the option of emergency credit.

With the smart meter rollout in full swing, more and more prepayment meters are being set up as smart meters too. This makes it much easier to top-up, as rather than having to pop to the shops and add credit to your key or card, many energy providers offer the option of doing so through a smartphone app or online.

Prepayment meter pros and cons

Next, let’s take a look at some of the advantages and disadvantages of using a prepayment meter for your energy supply.

What are the advantages of using a prepayment meter?

  • Keep on top of your credit: Budget how much you’re spending on energy ahead of time and avoid the possibility of a nasty shock when bills arrive at the end of the month.
  • Top-up online: Many energy suppliers now offer smart prepayment meters, which allow the user to top-up remotely, using a smartphone app or online login.

What are the disadvantages of prepayment meters?

  • Inconvenience of topping up: If your supplier does not offer smart prepayment meters and the ability to top-up online, it can be a pain to have to go to your local PayPoint, Payzone or Post Office to add credit.
  • Potential to lose your top-up key or card: It seems obvious but if you lose your top-up key or card you could be left without power and may be charged for a replacement if you’re unable to find it.
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How and where to top up your prepayment meter

There are a few different ways to top up your prepayment meter:

  1. All prepayment energy suppliers allow topping up at your nearest Post Office or PayPoint location.
  2. Some suppliers like Npower use PayZone, which works the same way as PayPoint.
  3. Many energy providers like EDF, Ovo Energy, British Gas and EON will allow you to top up online, by phone, text message or with a mobile app. They can do this thanks to smart prepayment meters.

Step 1: Top Up at Post Offices, Shops, by Phone or Online

Before heading out, make sure to leave your card or key inserted in your meter for a full minute.

  • Post Office, PayPoint and PayZone: Take your key or card to a local Post Office, PayPoint or PayZone outlet and request your desired top-up amount. It’s important to keep the receipt so you have a record of what you paid.
  • Phone, Online and Mobile Apps: Make sure you have your account number, key or card number and some other details like your email ready. You will need to have a Smart Prepayment (PAYG) Meter installed so its best to check with your energy supplier to see if you can top up without having to go to the Post Office or a shop.

How much can I top up?

Generally, the minimum top-up amount is between £1 and £5 while your top-up card or key is designed to hold up to £249 (card) or £250 (key) worth of credit. Bear in mind, when you go to the Post Office or a shop, you can only buy up to £50 of credit for your electricity and £49 for gas at any one time.

Step 2: Load the credit onto your Prepayment Meter

If you have a smart prepayment meter, you are done. After topping up with the mobile app, online, by phone or even in a shop or post office, the credit will show up on your meter within 45 minutes at most.

Even if there is a reception issue preventing smart top-ups, you can still manually enter a code (from a paper or text receipt) into the smart meter to credit your account.

If you don’t have a smart prepayment meter, there are a couple of extra steps:

Gas Prepayment Meters

Always check top-up details with your energy supplier.

  • Insert your card and leave it there for a minute while the credit transfers to the meter.
  • Some gas suppliers like Npower and British Gas require you to press the red A button to credit your meter.
  • Other suppliers do not, unless you need to restart your gas supply or use emergency credit.
  • The on-screen will confirm the new balance either way.

Electricity Prepayment Meters

Always check top-up details with your energy supplier.

  • Insert your card and leave it there for a minute while the credit transfers to the meter.
  • Some gas suppliers like Npower and British Gas require you to press the red A button to credit your meter.
  • Other suppliers do not, unless you need to restart your gas supply or use Emergency Credit.
  • The on-screen will confirm the new balance either way.

I’ve topped up but the credit hasn’t gone on to the meter

There are three possible reasons that your top-up is not working:

  1. Prepayment key or card needs to be cleaned or is faulty. You can clean your key or card with a dry cloth. If that doesn’t solve the problem and you are inserting your key or card correctly, then contact your energy supplier to get a replacement key or card.
  2. Credit was not loaded correctly. You will see ‘Credit Failed’ written on your receipt. If this happens, take your key or card back to the same Post Office or shop so they can load it up correctly at no extra cost to you.
  3. Prepayment credit bought from a scammer. Some criminals are tricking people by offering prepayment top ups that are too good to be true. Their cloned keys and cards are immediately flagged by energy companies. Unfortunately, customers who fall for these dirty tricks have no recourse and have to pay a second time for the real top up from their energy company.

Emergency Credit

Gas flame

Just like driving on empty in cars, most - though not all - electricity and gas meters have a reserve called emergency credit, so that you don’t immediately get cut off from your gas or electricity supply.

Emergency credit, between £5 and £15 worth, does not kick in automatically. You have to manually activate it before your credit runs out, so that everything in your home stays on.

Usually, it involves pushing a red button on your meter but you should check with your energy supplier as instructions can vary by company. The full emergency credit amount will be used when activated.

Be aware that once you turn on emergency credit, you will owe the emergency credit amount (anywhere between £5 and £15) to your energy provider moving forward. You will pay it off automatically with your next top-up, which means that the new top-up amount needs to account for the owed emergency credit.

If you turn on emergency credit, you should top up with a £15 or more credit, when you can, so that you pay off the emergency credit and still have some credit afterwards.

Emergency credit is a one-time deal which can only be paid back and never replenished, unfortunately.

I can’t afford to top-up my prepayment meterIf you’re having a hard time trying to meet your energy costs, many suppliers will offer emergency help, while there are also a number of energy schemes for those most at risk of fuel poverty.
To find out more and see if you’re eligible visit our guide to Energy Grants and Schemes

What should I do if I lose my card or key?

Most suppliers will charge anywhere between £5 and £10 for a replacement if you lose your prepayment key or card. The replacement charge will often be covered by top-ups and most suppliers spread out the cost over several top-ups to make it easier to pay off.

Moving into a house with a prepayment meter

If you have just moved and your new home has a prepayment meter, there are a few things to bear in mind:

  1. You could be liable for the previous resident’s debt unless you contact the energy supplier to reset the meter so you don’t end up footing the bill.
  2. If the previous tenant or occupant did not leave you with the top-up key or card, you cannot just borrow or use different keys or cards because they will not work.
  3. Contacting the energy supplier is the only way to get your meter and top up method sorted out. Have your supply and meter numbers (MPAN and MPRN) handy when you speak with them.

How to remove a prepayment meter

If you’ve recently moved into a property with a prepayment meter and want to switch to a credit meter instead, you can request to swap them out. You may be charged a fee for this, so always check the terms and conditions before doing so. If you are renting, make sure you have permission from your landlord first.


How to read a Prepayment Meter

The main reason to take a prepayment meter reading is if you are moving home and need to close your account. Not all prepayment meters need to be read because your energy supplier will receive readings every time your prepayment key or card is charged.

Electric Prepayment Meter Instructions

  1. Press the Blue button on the front of the prepayment meter.
  2. With each button press, you will move to a different readout screen. They either go from letters A to T or from numbers 1 to 9, depending on your prepayment meter model.
  3. Press the button until you get screen H or 5 to get your meter reading. You will want to take down all the numbers even if there are zeros in front.
  4. Be aware that the meter reading only shows for a little while before switching back to the first screen. If that happens, all you need to do is move through the screens to get back to the one you want. Just make sure that you go back to the same one to avoid making a mistake that could cost you a lot of money.
  5. If you have an Economy 7 tariff, you will need to press on the prepayment meter button to move to screen J to get the correct off-peak night meter reading.

Gas Prepayment Meter Instructions

  1. Press the Red button.
  2. If your gas prepayment meter has a window located on top of the LCD display, that will show the meter reading.
  3. Other gas prepayment meters will have two displays, in which case, the left one will give you the meter reading.
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