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25 March 2021

How to choose the best energy company

Why you should consider more than just price when you choose your energy company. Use our research to find the best gas and electricity firm for you.
Energy bills 470956
SI
Sarah Ingrams

There are more energy companies to choose from than there are weeks in the year – and new gas and electricity suppliers launch fairly regularly in Great Britain. But the last few years have also seen several energy companies go bust, so picking one from the ever-changing list can be daunting.

More than half of us still buy our energy from one of the original big suppliers. All of them ranked in within the bottom seven of the 25 energy suppliers included in our latest energy companies satisfaction survey.

So there’s every reason to shop around to find an energy supplier to suit you, whether you’re looking for the cheapest deal on the market, renewable energy, great digital tools, one which offers the latest in smart home technology, innovative tariffs or something else.

Our energy satisfaction survey results are a unique insight into what customers really think of their energy suppliers. You can use this, plus our expert advice, to cut through marketing jargon and money-saving claims to find the best energy suppliers.

Use our research below to help find the best energy firm for you. Or if you just want the cheapest, compare gas and electricity prices with Which? Switch.

Looking for the best and worst energy firms in Northern Ireland? Head to our guide to Northern Ireland electricity and gas companies.

Renewable energy companies

A large and growing number of energy companies, and even more tariffs, are branded as ‘green’. But there’s no set definition of what ‘green’ means, so it’s worth checking before you sign up to make sure you’re getting what you expect.

Ecotricity, Good Energy and Green Energy UK are the most longstanding renewable energy companies. They only sell tariffs backed by 100% renewable electricity and supply a proportion of ‘green gas’ (from biomethane). Ecotricity uses money from its customers' bills to fund new renewable generation. Good Energy buys its electricity from more than 1,600 independent renewable generators. Green Energy UK sells 100% green gas.

Other energy suppliers selling only tariffs with 100% renewable electricity include Bulb Energy, Co-operative Energy, Eon, Octopus Energy, Ovo Energy and So Energy (this is not an exhaustive list).

You'll find other energy firms selling tariffs with 'zero carbon' electricity. These include British Gas and EDF Energy. It usually means that their electricity comes from either renewables or nuclear power.

The majority of energy firms offer a tariff with 100% renewable electricity, though their other tariffs may have a different fuel mix.

Additionally, some suppliers sell a proportion of green gas (usually from biomethane) and invest in carbon reduction or carbon offset schemes for their gas tariffs.

Online energy and smart home technology

Some newer energy firms claim to be digitally focused and pride themselves on slick online service, apps and user-friendly websites.

For example, Pure Planet provides online-only customer services. Boost and Utilita provide top-up for prepayment customers via their apps. Ovo Energy’s online account allows customers to see how much they’re spending on running different types of home appliances.

Energy companies are now installing smart meters (which should be second-generation meters). They come with an in-home digital display, plus many suppliers also offer an app and online account through which you can see and use your energy use data. Check our What is a smart meter? to find out what you need to know before you get a smart meter.

Increasing numbers of suppliers are selling smart-home products, or including them free when you sign up to certain tariffs. For example:

  • British Gas sells smart products from its Hive brands, including smart thermostats, smart plugs, motion sensors, smart light bulbs and home cameras
  • EDF Energy sells Nest and Tado smart thermostats, as well as smart plugs, lightbulbs and radiator thermostats from a range of brands
  • Eon sells Tado smart thermostats and smart radiator controls
  • SSE offers a Google Nest Thermostat E with one of its tariffs
  • Scottish Power sells Honeywell smart thermostats

Energy and broadband bundles

Utility Warehouse was the original company to bundle multiple home services together in one monthly bill. You can buy broadband, home phone, mobile and insurance packages from it, as well as energy.

But it's not the only one. SSE and Shell Energy also sell broadband.

Boiler cover and insurance

Several of the bigger energy companies, including British Gas, Ovo Energy, SSE and Scottish Power, sell boiler cover which often comes with call-out repair services if yours breaks. 

Before you buy, read our advice on how to choose the best boiler cover.

Innovative energy tariffs

The majority of tariffs are structured around a daily standing charge, plus a set rate for each unit of energy you use. The charges and rates are different for gas and electricity. Find out how to get the best energy deal. But there are different types of tariff if you look for them, mostly enabled by smart meters.

Smart tariffs require you to have a smart meter installed. Sometimes they offer a discount compared with a regular meter tariff. Other smart tariffs give lower prices for electricity used at specific times of day. 

Octopus Energy's Agile Octopus tariff is one of these. It tracks half-hourly wholesale prices and updates its rates daily. So customers can save money by using electricity at times when it's cheaper. Occasionally energy prices fall below zero and customers get an alert so they can take advantage.

The government expects smart tariffs to become more widespread as smart meters are further rolled out, more people have electric vehicles and electricity demand increases.

Tracker tariffs pass the cost of wholesale energy directly onto the customer. The aim is to make the price you pay for energy much more transparent. When the wholesale cost drops, you’ll see the savings passed on. But if it increases, you’ll pay more too. 

Octopus Energy and Utility Point Utility Point are among suppliers offering this type of tariff, though they’re all slightly different.

EV tariffs usually also require you to have a smart meter, as well as an electric vehicle charger. Customers can get cheaper electricity for a few hours overnight, usually, to help charge their car's battery for less. British Gas, EDF Energy,Eon, Octopus Energy and Ovo Energy all sell EV tariffs, and the choice of suppliers is growing.

also offers an unusual way of buying energy. Customers buy ‘powerpacks' of energy in advance. They’re usually discounted compared with the usual rate, so the idea is that you can save money by buying upfront.

Pay-as-you-go energy

Boost Energy, E and Utilita focus on customers with prepayment energy meters (though you can also be a customer of Utilita with other payment methods).

Customers with smart meters can top-up online, using a smartphone app, via text message and point as well as at Paypoint outlets.

If you have a PAYG energy meter, or are considering one, read our advice on is a prepayment energy meter right for you?