TL;DR
SMETS2 (Smart Metering Equipment Technical Specifications 2) is the second generation of UK smart meters, deployed from 2018 onward. Unlike SMETS1 meters, SMETS2 meters communicate via a central data network managed by DCC and continue to work in smart mode when you switch energy supplier. Installation is free through your energy supplier. SMETS1 meters can be upgraded to SMETS2 functionality remotely.
Last reviewed: June 2026
Smart meters replace traditional gas and electricity meters and send automatic readings to your energy supplier over a wireless network. You no longer need to submit manual meter readings, and you receive near-real-time information about your energy use on an in-home display (IHD) device. The UK government has run a national smart meter rollout since 2016, with all households offered a smart meter by energy suppliers.
Two generations of smart meter have been deployed: SMETS1 (first generation) and SMETS2 (second generation). Understanding the difference between them matters because SMETS1 meters had a significant limitation that caused problems for millions of households.
KEY FACTS
- SMETS2 meters communicate via the DCC (Data Communications Company) national network.
- SMETS2 meters retain smart functionality when you switch energy supplier.
- SMETS1 meters were enrolled onto the DCC network from 2019, restoring smart functionality for most.
- Smart meter installation is free; suppliers cannot charge for the meter or installation.
- The in-home display (IHD) shows near-real-time energy usage in pounds and pence.
- You have the right to refuse a smart meter installation under current UK rules.
SMETS1 vs SMETS2: the key difference
SMETS1 meters, installed from around 2012 to 2018, communicated directly with the installing supplier's network using proprietary technology. This worked fine as long as you stayed with the same supplier. However, when you switched to a different energy supplier, the new supplier could not communicate with the SMETS1 meter using its own system, and the meter effectively reverted to a traditional dumb meter. You would have to go back to submitting manual readings.
This problem affected millions of households and was a significant barrier to switching suppliers, since customers with SMETS1 meters risked losing smart functionality. It also undermined one of the core benefits of the smart meter rollout: enabling easier and more accurate switching between suppliers.
SMETS2 meters, deployed from 2018 onward, solved this problem by communicating via a centralised network managed by the Data Communications Company (DCC), a licensed company authorised by Ofgem. The DCC network is a single, interoperable platform that all energy suppliers connect to. When a customer with a SMETS2 meter switches supplier, the new supplier simply connects to the same DCC network to communicate with the meter. Smart functionality is preserved through the switch.
The DCC and how it works
The Data Communications Company is a regulated entity authorised by Ofgem to manage the national smart metering data and communications infrastructure. It was established specifically to create a supplier-independent communication layer between smart meters and energy suppliers, network operators and other authorised parties.
Data flows via the DCC network in near real time. The meter sends consumption data (typically every 30 minutes for electricity, hourly for gas) to the DCC, which passes it to the relevant supplier. The IHD in the home receives a direct wireless signal from the meter and updates every 10 seconds, giving a live view of energy use.
The DCC network also enables remote commands: suppliers can remotely change meter settings (such as switching between credit and prepayment modes), issue software updates to meters, and in some circumstances remotely disconnect supply (subject to regulatory rules). These remote capabilities reduce the need for engineer visits for routine changes.
What you see on the in-home display
The in-home display (IHD) provided with a smart meter installation shows your current electricity usage (and gas usage if you have a smart gas meter too) in near real time. It typically displays current usage in kilowatts and the estimated cost in pounds and pence per hour at your current tariff rate. Some IHDs also show daily, weekly and monthly totals and allow comparison with previous periods.
The IHD connects to the smart meter via a home area network (HAN), a short-range wireless connection that typically works within about 30 metres of the meter. If the IHD is placed too far from the meter (through thick walls or across multiple floors), the signal may be intermittent. Most IHD issues can be resolved by moving the device closer to the meter.
The IHD is provided free with the smart meter installation. If it stops working, contact your energy supplier for a replacement. Suppliers are generally obliged to provide a functioning IHD as part of the smart meter service.
SMETS1 meter upgrade to DCC
From 2019, SMETS1 meters began to be enrolled onto the DCC network, restoring smart functionality even for customers who had switched supplier. This enrolment process was done remotely without the need for an engineer visit in most cases. By 2023, the majority of SMETS1 meters in Great Britain had been enrolled onto the DCC network.
If you have a SMETS1 meter and it is showing as a dumb meter (requiring manual readings), contact your current supplier to check whether your meter has been enrolled onto the DCC network. If it has not, they can request enrolment. Alternatively, you can request a free upgrade to a new SMETS2 meter.
Your rights regarding smart meters
Under current Ofgem rules, you cannot be forced to have a smart meter installed. Suppliers can offer smart meters and encourage uptake, but a household that declines must still receive energy supply on a traditional meter. Suppliers may not withdraw tariff options solely because a customer refuses a smart meter, though in practice the range of tariffs may differ.
If you have a smart meter and want to switch back to a traditional meter, you can request this from your supplier, though they are not obliged to agree and may charge for the reversal. The more common scenario is that customers want smart meters for the convenience and real-time data, not the other way around.
Data collected by smart meters is subject to the UK GDPR and the Smart Energy Code. Half-hourly consumption data is more granular than monthly billing data and can in principle reveal household patterns. Customers can choose what data is shared with their supplier and on what frequency, with options typically ranging from half-hourly to daily to monthly transmission.
Frequently asked questions
Will my smart meter stop working if I switch supplier?
If you have a SMETS2 meter, no. SMETS2 meters use the DCC network and retain smart functionality through a supplier switch. If you have a SMETS1 meter that has been enrolled onto the DCC network, it should also retain smart functionality. If you have an old SMETS1 meter not yet enrolled, contact your new supplier after switching to arrange enrolment or a free upgrade.
Is a smart meter installation free?
Yes. Energy suppliers cannot charge customers for smart meter installation. The cost is recovered through network charges and supplier operating costs across the customer base. There is no upfront cost to the household for the meter, installation or the in-home display.
Can I get a smart meter if I am on a prepayment tariff?
Yes. Smart prepayment meters (sometimes called smart pay-as-you-go meters) allow prepayment customers to top up remotely via an app or online, rather than visiting a shop or using a key or card. They also allow the DCC to remotely switch the meter between credit and prepayment modes, which can help customers transitioning between payment types.
What is the RTS switch-off and how does it relate to SMETS?
The Radio Teleswitch Service (RTS) switch-off refers to the decommissioning of an older signal used by Economy 7 and similar off-peak meters. RTS meters are distinct from SMETS smart meters and are being replaced separately. If you have an Economy 7 meter, check with your supplier whether your meter uses RTS and arrange an upgrade if so.
