What is a smart meter?

Smart meters measure your gas and electricity use, like traditional meters do, and send the readings to your energy supplier automatically.

They give both you and your energy provider accurate and regular updates on your energy use. This means that your bills should be accurate without you needing to send meter readings.

Smart meters usually come with a smart meter monitor – a small display that shows how much energy you use in real time and how much it's costing.

You'll often be able to see your energy use and spend in your energy supplier's online account or app too. Knowing this should help you to better control your energy use. 

Find out what to expect from a smart meter installation.

How do smart meters work?

Smart meters send usage data to your energy supplier using wireless networks, similar to mobile phone networks. 

Your gas smart meter, electricity smart meter and smart meter monitor (also called an in-home display) talk to each other wirelessly using a communications hub. 

This is usually attached to or part of your electricity smart meter. It also sends your energy use data to your supplier using the smart meter wide-area network.

Electricity smart meters are connected to the mains and monitor how much power you're using in real time. Gas smart meters are battery powered and 'asleep' for most of the time, waking up every half hour to take a reading.

How smart meters communicate

1. Smart meters take a reading of your gas and electricity use and turn it into an encrypted 'message'.
2. The communications hub creates a wireless home area network and receives messages from your smart meters.
3. The hub sends them to your smart meter monitor.
4. It also sends them, via the wide area network (made up of mobile phone or radio masts), to the Data and Communication Company's (DCC's) servers. 
5. The DCC sends the message to your energy supplier and your local energy network operator.
6. Energy networks, which manage the wires and pipes to distribute gas and electricity, use the data to improve their systems. 
7. Your energy company uses the data to bill you and show how you're using energy in your online account and app.

You’ll get a different communications hub depending on where you live. In the south and central areas of Great Britain, hubs use cellular and wireless mesh technology to communicate with the DCC’s central network. Further north, they communicate via long-range radio.

Smart meter monitors use different technologies to connect to your communications hub too. Most homes get a standard, ‘single-band’ hub, which work in 70% of properties. If you’re not among these, you’ll most likely get a dual-band communications hub, as these should work in an additional 26-28% of homes. 

The latest development is ‘alt HAN’ communications hubs, which make communication possible in homes where gas and electricity meters are far apart or where there are particularly thick walls, as well as in high-rise flats and rural areas. These hubs will help the final 2-4% of homes. Ask your energy supplier about these if you think you'll need one.

Smart meters are different from energy monitors. While energy monitors can show you how much electricity you’re using, they don’t communicate this information to your provider.

Find out how to use your smart meter data.

How to read a smart meter

You shouldn't need to take meter readings unless your smart meter has stopped working in smart mode (and isn't sending readings to your supplier).

Some smart meter monitors show your meter readings. You’ll usually need to scroll through the different screens to find them.

You can also get your meter reading from your smart electricity meter and gas smart meter. Most have a button to illuminate the digital display so you can read the numbers. 

If you're not sure, check the instructions your smart meter installer gave you, look on you energy supplier’s website or ask it for instructions.

Next, find out how to use your smart meter reading data.

If you have a traditional meter, find out how to read your gas meter or how to read your electricity meter.

Do I have to have a smart meter?

No, you don't have to accept a smart meter if you don’t want one.

Energy companies must take ‘all reasonable steps’ to install smart meters in their customers’ homes. This is set out in the conditions of their licences to supply gas and electricity. 

Energy firms have annual installation targets, which are set by a formula devised by government. Companies that don’t meet their targets can face penalties, so they’re under pressure.

Energy companies also have to take ‘all reasonable steps’ to install smart meters where they’re replacing an old meter, or installing a meter for the first time (for example in a new-build home).

If one is being installed in your home but you're not interested in having a smart meter, ask your energy supplier if it can be set up in traditional mode, with its communications turned off.

But if your energy firm has contacted you to change your meter because it needs replacing (ie it’s too old), then you should get it replaced as it could be a safety hazard if you don't.

What is the point of smart meters?

Smart meters can make money and carbon savings for you, your energy company, and the wider energy system when used correctly.

They remove the need for estimating your energy use, give you access to tariffs that reward you for using power outside peak times, and show you which appliances are costing you most.

Smart meters are a key part of the wider electricity system changing from passive electricity grids to ‘smart grids’. 

Smart grids use digital technology, so network operators can predict much more accurately how much electricity is needed by the country, and when, so they can better match supply with demand.

Network operators use information from smart meters to detect power cuts faster and give engineers better information about what caused them.

Read our tips on how to use your smart meter data. 

Advantages of smart meters

• More accurate bills. Suppliers always have your most up-to-date meter readings so don't need to estimate. 
• You don't need to send meter readings. They're sent automatically by your smart meter every half hour or daily (or monthly in some circumstances).
• Monitor your usage and spend quickly and easily via your smart meter monitor or an app. Seeing the energy use and cost of using some appliances might prompt you to be more efficient.
• Prepayment customers won't miss out on support. Energy Bills Support Scheme payments were added automatically to the accounts of smart pay-as-you-go customers the winter before last. Those with traditional prepayment meters had to take vouchers to top-up points. Nearly two million weren't claimed.
• You might save money. Acting on information from your smart meter could help you be more efficient and cut your bills. 
• Access new tariffs that charge you less for electricity you use at times when demand is low, or Smart Export Guarantee tariffs for solar panel owners.
• Prepayment customers can set automatic top-ups. Your smart meter monitor can also show your credit balance and alert you when it's running low.
• Help decarbonise our power system. Knowing electricity use every half hour helps network operators better manage demand and rely less on fossil fuels to meet times of high electricity demand. Smart tariffs can encourage homes and businesses to use more power at times when it's greenest.

Disadvantages of smart meters

• Smart meter monitors can stop working or aren't updated. Suppliers should replace faulty monitors for 12 months. Contact your supplier if your monitor isn't showing correct information. You should keep your monitor close to your smart meters for best signal.
• Early smart meters lost functionality when you switched supplier. This meant you had to send meter readings again and your smart meter monitor may have stopped working. Nearly 12 million of them have now been reconnected to the smart meter network, with nearly 3.5 million still operating in 'traditional mode'.
• Your meter could be switched to prepayment remotely. It is technically possible to change how you pay remotely but the rules are the same whether you have a smart or traditional meter – pay-as-you-go for debt collection should only be a last resort. Find out more about whether prepayment is right for you.
• Smart meters struggle in some properties. Weak signal can mean smart meters struggle to communicate with your supplier effectively. The smart meter network now reaches 99.3% of homes and suppliers can install additional aerials to boost signal.

Find out more about common concerns with getting a smart meter fitted.

How to top-up your smart meter

If you pay as you go and have a smart meter, you won't need to go to the shop to top-up your meter. Instead, depending on your supplier, you can top-up using:

• your online account
• your energy company's app
• by phone.

Your credit will often be added to your meter automatically. 

You can also add your top-up manually via your smart meter. Some smart meter monitors can also be used to add your top-up. 

You'll need the code from your receipt or payment confirmation. Exactly how you do this can vary by supplier and meter so check your supplier's website for instructions.

You can still top up at the shop if you want to. Some suppliers will send you a new top-up card with your smart meter.

Find out whether you should get a smart prepayment meter.

Video: Smart meter myths debunked

In this video, our experts cut through the conspiracy theories about smart meters. If you're concerned that smart meters could be a risk to your health, your privacy or your bills, discover whether or not you really have anything to fear.

Smart meter roll-out in Great Britain

Nearly two thirds of energy meters in homes are now smart meters, according to government data published in August 2024. That's around 34 million smart meters.

Energy firms have until the end of 2025 to fit smart meters in 75% of homes.

But over 3.5 million of them are working in 'traditional' mode. That means they aren't sending meter readings automatically to the energy supplier.

Energy suppliers must take 'all reasonable steps to ensure that they are able to communicate with their customers' smart meters', energy regulator Ofgem told us.

Find out what to do it your energy supplier isn't getting meter readings from your smart meter.

SMETS2 smart meters and SMETS1 smart meters

There are two types of smart meter: 

• first generation (SMETS1)
• second generation (SMETS2). 

SMETS stands for Smart Metering Equipment Technical Specifications.

Energy companies have been installing second-generation smart meters for several years. These are automatically connected to the smart meter network so all energy firms should be able to operate them.

When energy suppliers began installing smart meters, they fitted first-generation meters. These work in the same way as more modern meters but they can lose their smart functions when you switch supplier. 

Work is well underway to connect first generation meters to the smart meter network where they'll work like any other smart meter. If your smart meter can't be connected, it should be replaced. 

Find out more about smart meter problems and how to solve them. 

Smart meters in Northern Ireland

Smart meters aren't currently being installed in Northern Ireland but that is set to change.

In July 2023, the Department for the Economy announced that it is developing a 'plan for the implementation of electricity smart meters and systems'. 

Its analysis recommends that a roll-out over six years, starting in 2027, would be most cost effective.

There are no plans to install smart gas meters.

Read more about Northern Ireland electricity and gas companies.

Can rural homes and flats have smart meters?

Almost all homes should be able to have smart meters. The smart meter network covers 99.3% of homes across Britain, according to Smart DCC (which operates it). 

Where the signal is weak, energy suppliers can install additional aerials to boost it. You may need to ask your supplier about these.

You may have been told you had to wait longer for a smart meter if:

• you live in a rural area with weak signal
• you live in a high-rise block of flats
• your home has very thick walls
• your gas and electricity meters are far apart.

These factors meant that your gas and electricity meters may struggle to communicate with each other, or with the communications hub that sends your energy-use data to your energy firm. 

Contact your supplier to check whether it's now possible to fit a smart meter in your home.

Can I have a smart meter if I rent?

Yes, if you rent your home, you can get a smart meter installed as long as you're paying the gas and electricity bills directly to the supplier. 

If your landlord pays the energy bills, it's their decision whether to get smart meters.

Check your tenancy agreement if you’re not sure. It’s a good idea to tell your landlord before you get a smart meter installed, even if your tenancy agreement doesn’t say you have to.

Find out more about getting a smart meter installed in a rented home.

Do smart meters save money?

Automatic meter readings sent by your smart meter mean more accurate bills for you. 

Companies are expected to make savings from receiving fewer customers enquiries and making fewer home visits to read meters. In principle, they should pass on these savings to customers. 

Right now, the financial benefits are most obvious if you have an electric vehicle (EV) that you charge at home.

Specially designed tariffs give cheaper charging rates overnight, or respond to price signals to charge your EV whenever it's cheapest. 

If you don't have an EV you can still access tariffs and schemes that charge lower rates for electricty used at less popular times, or reward you for doing this. 

You might also save money by using your appliances more efficiently after seeing your energy use on your smart meter monitor. That will depend on how frugal you are already.

Follow our tips to become more energy efficient – see our expert advice on 10 ways to save on energy bills.

Are smart meters free?

You should not pay anything upfront to have smart meters installed. There is no upfront cost for your smart meter monitor either.

But energy companies shouldn't tell you that smart meters are ‘free’, because ultimately you pay for them indirectly, through your energy bills. This is how traditional gas and electricity meters are paid for too.

Do smart meters need wi-fi?

No. You don’t need wi-fi or a broadband connection in your home to have smart meters. 

Inside your home your smart meters communicate via a home area network, created by the communications hub installed with them. They use this to communicate with your smart meter monitor too.

Outside your home they communicate using a secure national wireless network used only by smart meters.

Can I switch energy supplier with a smart meter?

Yes. Having a smart meter does not stop you from switching supplier. 

There have been many reports of smart meters losing their smart functionality after switching supplier. They still measure your energy use but you have to take meter readings and send them to your supplier. Your smart meter monitor might stop showing your energy costs too. 

This issue mainly affected first-generation smart meters installed several years ago. 

Energy firms have been installing second generation meters in recent years which are not affected. 

Smart meters should make it quicker to switch suppliers as they can send information to a new supplier about your energy use instantly.

Find out what to do if your smart meter stops working and other smart meter problems and how to solve them.