Last updated: April 2026
A complete guide to smart meters in the UK — how they work, whether you should get one, and what happens when you switch supplier.
A smart meter is a digital gas or electricity meter that automatically sends readings to your energy supplier. It replaces your old mechanical meter and comes with an in-home display (IHD) that shows your energy usage in real time, both in kWh and pounds. Smart meters eliminate the need for estimated bills and manual meter readings.
There are two generations of smart meters in the UK. SMETS1 meters were installed from 2012 to 2018 and could lose smart functionality when switching supplier. SMETS2 meters have been the standard since 2018 and use a national communications network (DCC), meaning they continue working in smart mode regardless of which supplier you are with. Most SMETS1 meters are being upgraded to work with the DCC network.
Smart meters offer several benefits: accurate bills based on actual usage (no more estimates), real-time usage monitoring through the in-home display, easier supplier switching with automatic readings, support for smart tariffs with time-of-use pricing, and half-hourly data that helps you identify energy waste. Studies show that customers with smart meters and IHDs reduce their energy usage by 2-3% on average.
All UK energy suppliers are required to offer smart meters to their customers. Installation is free — you do not pay anything for the meter or the installation visit. Contact your supplier to book an installation. The visit typically takes 1-2 hours for a dual fuel (gas + electricity) installation. There is no obligation to accept a smart meter if you prefer to keep your traditional meter.
If you have a SMETS2 smart meter, it will continue working in smart mode when you switch supplier. Your new supplier will automatically receive your meter readings through the DCC network. If you have an older SMETS1 meter, it may temporarily revert to a traditional meter when you switch, requiring manual readings until the new supplier enrols it.
No, smart meters are not compulsory. Your energy supplier must offer you one, but you can decline. However, smart meters provide benefits like accurate billing and real-time usage data that can help you save money. There is no downside to having one installed.
Smart meter installation is free for domestic customers. The cost of the smart meter rollout is included in energy bills as part of supplier operating costs, so you pay for it indirectly whether or not you have one installed. Getting a smart meter does not add any additional charge to your bill.
Smart meters alone do not save money, but the real-time usage data they provide can help you identify waste and reduce consumption. Studies show average savings of 2-3% for customers who actively use their in-home display. Smart meters also enable access to smart tariffs like Octopus Agile, which can offer significant savings for flexible users.
Actionable tips to lower your gas and electricity bills without sacrificing comfort, from quick wins...
Understanding Your Energy Bill: A Complete UK GuideLearn how to read your gas and electricity bill, what each charge means, and how to spot errors or o...
Home Energy Efficiency: A Room-by-Room GuidePractical energy efficiency improvements for every room in your home, from the kitchen to the loft....
Information sourced from Ofgem, Citizens Advice, and DESNZ. Last updated April 2026.
AskUKEnergy is free to use. We may earn a commission if you switch through our links. This never affects the independence of our comparisons. Learn how we make money.