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8 May 2021

Six reasons to switch energy supplier

What you can do about high gas and electricity prices, cheap energy deals ending and poor customer service. Plus, the cheapest energy deals for May 2021
Two people sit at a table with a laptop and energy

If it feels like your energy bills are creeping upwards or you can't get hold of your supplier, there's no need to put up with it.

High gas and electricity prices and poor customer service are among the most common reasons people switch energy supplier.

More unusual reasons include frustrations with energy firms' websites, wanting to buy both gas and electricity from the same firm, or preferring a smaller energy firm.

Whatever your reason for switching, read our expert tips to find the best energy supplier for you.

Compare gas and electricity prices using Which? Switch, our free and independent energy comparison website, to find out how much you could save on your energy bills.

You can also phone us on 0800 410 1149 or 01259 220235.

1. Energy prices are too expensive

This was the number one reason people we surveyed wanted to switch energy supplier. How much you pay for electricity can rise for several reasons, including:

  • Your energy firm raised its prices
  • Your contract finished
  • You're using more gas and electricity
  • Your energy firm initially underestimated how much gas and electricity you would use.

There is a price cap on out-of-contract energy tariffs, limiting the amount energy firms can charge. But this cap changes every six months (the price cap increased in April) and your bills still depend on how much energy you use.

If you're out-of-contract with your energy firm, you could save up to £264 per year by switching to one of the cheapest deals on the market.

The saving is based on a household using a medium amount of gas and electricity*, switching from a tariff at the level of the price cap to the cheapest deal when we checked.

Keep reading to see the cheapest energy tariffs or find out how to switch energy supplier.

2. Your fixed energy tariff ended

Woman looking at an energy bill in a kitchen

Fixed deals are often one or two years' long. At the end of your contract, you'll automatically move onto your energy firm's out-of-contract tariff if you haven't chosen a new tariff.

Out-of-contract tariffs are usually pricier so you'll end up paying more.

You might find that your supplier isn't selling a tariff as cheap as your last one. If so, compare energy prices to see if another firm could save you money. Also check to see if your current supplier has a cheaper rate for new customers only - if so, you will usually need to sign-up for this using a price comparison website.

Find out: how to get the best energy deal

3. Poor customer service from your energy supplier

If your energy firm is driving you to distraction, you're not alone. Our latest customer survey on energy companies found sterling customer service from some firms, and two-star service from others.

See the best and worst energy companies to pick one with service its customers rate.

This year, we awarded two Which? Recommended Providers for energy:

  • Octopus Energy
  • Pure Planet

We only recommend energy firms which passed all of our tough assessments.

4. You found a better gas and electricity deal with another firm

Family sitting around a kitchen table

Even if you're satisfied with your supplier, it's worth keeping an eye on prices so you know whether you're still getting a good deal.

To get you started, here are the five cheapest energy deals widely available now. Savings are based on a household using a medium amount of gas and electricity*, compared with a tariff that costs the maximum permitted by the price cap.

If you use more or less energy than this, your costs and savings will be different. Use our free independent service Which? Switch to compare gas and electricity prices. Make sure you input your gas and electricity use over the last year in kilowatt hours to get the most accurate quotes.

Top five cheapest energy supplier deals in May 2021

CompanyTariffAnnual price (medium user)Fixed/ variableExit feeSavings compared with the price cap
Orbit EnergySpring Vari-Save Extra£874Variablen/a£264
Outfox the MarketSpring 21 Variable£908Variablen/a£230
Avro EnergySimple and GoSwitcher£914Fixed£30 per fuel£224
Goto EnergyStandard Variable Tariff£932Variablen/a£206

All tariffs have direct debit payments and paperless bills and are correct on 5 May 2021.*

5. You want to be more sustainable

Switching energy tariff can help cut your carbon footprint, but energy firms take different approaches to their renewable electricity, including:

  • Generating renewable electricity
  • Having agreements with generators to buy their power directly
  • Buying certificates to match customers' electricity use with renewable sources
  • A combination of these.

Some sell green gas or offset their carbon emissions.

Find out more about how to choose the best energy company.

6. Problems with bills or payments

Inaccurate or non-existent bills or payments that don't make sense are a quick route to frustration.

The best energy firms in our energy survey gained five stars for the accuracy of their bills, while a few managed just two stars for producing clear bills.

If you think your bill is incorrect, contact your energy company and ask it to explain. It should be able to tell you how it has arrived at its figures and, if your payments have increased, explain why. Some online accounts have extra detail about how your bill is calculated.

If you are unable to resolve your query, escalate it as a complaint. Energy firms must set out their complaints process online (and usually on the back of your bill). If you cannot resolve it within eight weeks, you can take your complaint to the Ombudsman.

Which? energy research

In September 2020, we ran an online survey of 7,460 members of the general public who are responsible for paying gas or electricity bills in their household. We asked those who had switched energy company in the last four years why they wanted to leave their previous supplier.

*Prices are based on widely available dual-fuel tariffs, paying by fixed monthly direct debit, with paperless bills. Energy use is based on Ofgem's annual average figures for a medium user (12,000kWh gas and 2,900kWh electricity).

Comparisons are based on the current price cap, correct at 1 April 2021.

Data is from Energylinx and correct on 5 May 2021. Prices given are averages across regions, rounded to the nearest whole pound.