The main reason to switch suppliers is, quite simply, to save money. Once your contract ends with any particular supplier, they will continue to supply energy to your home, but you’ll likely be paying a lot more than you need to for it.
This is because suppliers invariably roll their customers onto their most expensive tariffs once their initial contract has ended – which usually lasts 12 months.
If you’ve not switched your energy supplier for a few years, or even if you’ve never switched at all, the chances are that you could be saving hundreds of pounds a year by finding a cheaper energy deal. Compare energy suppliers now to see how much you could save.
Choosing a new supplier can be as simple as picking the cheapest plan on offer in your area. But providers differ on more than just price. We've put together some pointers explaining the kinds of things you should consider below to help you make your decision:
Ultimately, you should go with whichever supplier will offer you the right deal at the right price. Most people in the UK are with one of just a handful of large suppliers, usually referred to as the 'big six'*. This is more out of habit than anything else - it's easy to gravitate towards big names.
This isn't to say you won't get a good deal from a big six supplier (far from it), but it is always worth looking further afield, particularly if you've got specific requirements like wanting a fully green supplier.
*With recent mergers, the big six isn't really a 'six' any more - read our guide on the big six and large suppliers for more information.
Domestic energy usage accounts for a huge portion of our national greenhouse gas emissions, and so choosing a green supplier for your home can make a big difference.
The gas and electricity your home receives comes from the national grid. This doesn't change based on your supplier. But each supplier puts energy from different sources into the grid, and green suppliers are those that provide wholly renewable electricity (and carbon offset gas). You can check each supplier’s energy fuel mix on their individual pages.See deals from green suppliers
In order to pick a supplier based on their green credentials, you'll need to check where their sourcing their energy from. Each supplier is obliged to publish fuel mix data after a certain number of years, and we've collected balances for the top 10 here:
Hopefully you won't have to deal with your supplier's customer service team very often if at all. But if you do, you want it to be as smooth an experience as possible. No lengthy waits on hold, no back and forth with a robotic online text service without any solutions to your problems. We've compiled a list of the best suppliers by customer service as rated by Which? in 2023:
|Which? customer score
When you compare with us, we can show you results from the whole of the market, including the suppliers that we are unable to switch you to right away.
|Taken over by Octopus Energy in 2018, Affect Energy still supplies 100% renewable energy to over 20,000 customers under its brand name.
|A not-for-profit supplier based in Islington, London, Angelic Energy’s customers were taken on by British Gas in September 2020.
|Once highly-rated for its customer serice, Avro Energy went into administration in 2021, with its customers being taken on by Octopus Energy.
|Supplies 100% green electricity generated from solar and wind farms based in the UK.
|Supplying renewable gas to domestic customers, Better Energy was taken over by PFP Energy in 2020.
|Owned by OVO Energy, Boost Power specialises in pay as you go tariffs, providing affordable energy to prepayment customer
|Despite selling its residential accounts to Together Energy in 2020, Bristol Energy continues to supply 100% renewable energy under its brand name.
|As one of the largest six energy companies in the UK, British Gas, provides power to millions of homes every day.
|Bulb was a rapidly-growing 100% renewable energy supplier when it was taken over by Octopus Energy in December 2022.
|Cardiff Energy Supply
|Had less than 1,000 domestic customers when it was taken over by SSE in 2019.
|Co-op Energy have partnered with Octopus Energy, committing to fairly priced and competitive services built on strong community values.
|Daligas was one of the UK's few gas only providers before it went bust in 2021, when its 9,000 customers were taken over by Shell Energy.
|E.ON is one of the largest energy providers in the country, providing power and heating to around 5 million homes.
|Previously partnered with Robin Hood Energy, EBICo formed a new partnership with Octopus Energy in 2021 and continues its dedication to tackling fuel poverty.
|After going bust in January 2019, Economy Energy’s 235,000 domestic customers were taken on by OVO Energy.
|Think of yourself as environmentally aware? Ecotricity is definitely a supplier worth considering.
|EDF Energy supplies 1/5th of the UK’s electricity supply.
|Enstroga Energy is a popular energy supplier in a number of European countries, but it's UK branch was taken over by E.ON Next in 2021.
|Ireland's state-owned supplier of renewable energy is now a part of So Energy.
|Had around 108,000 customers when it went bust in November 2018, and its customers were moved over to Scottish Power.
|Formed as a partnership between OVO Energy and Cheshire East Council, Fairerpower is a not-for-profit energy supplier with affordable tariffs.
|An independent energy supplier that went bust in May 2018, with its 300,000 customers taken on by Octopus Energy the following year.
|Used to offer just one gas or electricity tariff, but went bust in 2018 to be taken over by Green Star Energy.
|Was a small, independent energy supplier that went out of business in 2016, with its customers switched over to Co-op Energy.
|Was a small energy supplier with just around 500 customers when it went bust in 2018, and was subsequently taken over by Octopus Energy.
|Formerly known as Green Energy UK, it claims to be the UK’s only supplier of 100% renewable gas and electricity, generating its power from a number of power stations across the country.
|Targeted at students and houseshares, Glide offers a single utility bill covering energy, water, broadband, and a TV licence, all equally shared between housemates.
|Was a small, independent energy supplier that went out of business in 2020, with its 9,000 customers transferred to Bulb Energy.
|A family-owned energy supplier founded in 2013 went out of business in 2020, with its 2,500 customers taken over by Octopus Energy.
|Founded in 1999, Good Energy was the UK’s first green energy supplier, providing 100% renewable electricity and carbon neutral gas for over two decades.
|Green Network Energy
|Green Network Energy made a name for itself for being a values-driven, environmentally responsible business, but it ceased trading in 2021 and was taken over by EDF.
|Green Star Energy started in 2013 and became a well-trusted green energy provider before being taken over by Shell Energy in 2019.
|Igloo Energy quickly gained popularity in the domestic energy market with high customer satisfaction scores before going bust in 2021, with its customers taken on by E.ON Next.
|Once one of the cheapest energy suppliers in the UK, Iresa Limited collapsed in 2018 and its customers were taken on by Octopus Energy.
|iSupply was a low-priced energy supplier offering 100% renewable power before being taken over by EDF in 2020.
|The supermarket giant Marks & Spencer teamed up with Octopus Energy in 2018 to form M&S Energy, providing 100% renewable electricity.
|One of the UK’s fastest-growing energy suppliers, it supplies gas to both domestic and business customers up and down the country.
|Traditionally one of the Big Six energy suppliers in the UK, its domestic supply brand wound down in 2019 and its customers migrated to E.ON, and it now focuses on providing gas and electricity to business up and down the country.
|When it comes to paving the way towards a greener future, Octopus Energy are leading the pack
|Priding itself on being one of the cheapest energy suppliers in the UK, Outfox the Market also offers 100% renewable electricity.
|OVO Energy is the biggest challenger to the so-called 'Big Six' energy suppliers, having taken over SSE's domestic energy services in 2020.
|Launched in 2017 and gaining around 350,000 customers, People’s Energy ceased trading in September 2021 and was taken over by British Gas.
|Launched as a partnership between OVO Energy and Peterborough City Countil, it collapsed in 2019 and its customers were moved over to OVO.
|Also known as Places for People Energy, it’s 82,000 customers were taken on by British Gas in September 2021 after the supplier ceased trading.
|Pure Planet was a digital-only energy supplier with around 250,000 domestic customers when it ceased trading 2021 and was taken on by Shell Energy.
|Launched in 2015 by Nottingham City Council, Robin Hood Energy focused on supplying cheap energy to local residents but was folded into British Gas in 2020.
|In 2011, Sainsbury's joined the ever-growing energy market via a partnership with British Gas, but it stopped taking on new customers in 2019.
|Scottish Power was founded in 2009 and supplies electricity and gas across the UK as one the nation's big six.
|Thinking about changing energy suppliers? Shell Energy is one of the UK's largest independent energy suppliers and it offers 100% renewable energy.
|So Energy prides itself on being among the simplest, most transparent energy providers in the market, offering 100% renewable power
|Previously known as LoCO2 Energy, Solarplicity went out of business in August 2019, and its 8,000 customers were moved over to EDF Energy.
|Formed as a partnership between Southend-on-Sea Borough Council and OVO Energy, it folded in 2020 and its customers were moved to British Gas.
|Spark was started by individuals from the letting industry who used this experience to sell energy mainly to landlords, letting agents, and tenants, but it folded in 2018 and its customers were taken on by OVO Energy.
|SSE was once the second largest energy supplier in the UK, but its domestic energy service taken over by OVO Energy in 2020.
|A subsidiary of SSE and one of the leading providers of renewable energy in Ireland, SSE Airtricity also provides gas and electricity to UK customers in Northern Ireland.
|SSE Southern Electric
|Part of the SSE group, SSE Southern Electric provides renewable energy to domestic customers in the south of England.
|A member of the SSE group, SSE SWALEC focuses on supplying energy to Wales and Merseyside.
|Using collective energy switching to offer cheap tariffs to groups of customers, The Big Deal currently has over 400,000 members.
|Together Energy was an affordable energy supplier dedicated to combating fuel poverty in Scotland until it ceased trading in 2022 and was taken over by British Gas.
|Was an ambitious supplier of 100% renewable energy until it went bust in 2020 and Scottish Power took over its domestic customers.
|If you are on the lookout for an affordable smart meter provider, then Utilita Energy will definitely meet your needs.
|Launched in 2018, Utility Point offered reward schemes for its 100,000 customers until it ceased trading in September 2021 and was taken on by EDF Energy.
|Utility Warehouse is a convenient option for homeowners that don’t want to deal with multiple suppliers.
|A not-for-profit energy supplier created by Robin Hood Energy and Leeds City Council, it went bust in 2020 and its customers were taken on by British Gas.
|A green energy supplier launched in 2018, Yorkshire Energy went bust just two years later and its domestic customers were taken on by Scottish Power.