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How to save on your energy bill

How to switch energy supplier

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How to switch energy supplier

Switching energy supplier could save you hundreds of pounds on your gas and electricity bill. So what are you waiting for? Follow our step-by-step guide to switching.

Make sure you're not paying more than you need to for gas and electricity. Use our expert advice to switch energy firm with confidence and choose a deal that’s right for you.

Most energy customers we’ve spoken to find switching supplier quick and straightforward. It can take as little as 10 minutes to choose your new supplier and tariff online, although it will take another 16-18 days on average for your supply to be switched to the new company.

Here, we set out the switching process, including what you’ll need and what to look out for, plus what to do if you have a problem.

  1. What you need in order to switch energy supplier
  2. Comparing gas and electricity prices
  3. What to check before you switch
  4. How long does it take to switch energy supplier?
  5. Will I get compensation if I have a problem switching?
  6. Switching energy supplier as a tenant

What you need in order to switch energy supplier 

The more information you can provide when you're switching tariffs, the more accurate your quote will be. Make sure you have the following information to hand.

Your full address

Prices vary by region, and some energy deals are only available in certain areas. So using your full address will make sure that the quotes you get are applicable to your home.

The name of your current gas and electricity supplier and tariff

You’ll need to provide these so that any savings estimates are based on the deal you’re currently paying for.

If you don’t provide the name of your current tariff, a price comparison website will often assume you’re on the standard or default tariff.  This may be more expensive than your current deal, which risks the site over-inflating how much money you could save.

Without the name of your current energy supplier, the default used may be the company that historically supplied your area. As with assumptions about your tariff, there’s a risk that this will make your savings look bigger than the reality.

To find out the name of your energy tariff, check your latest bill, look at your online account or contact your supplier.

How much gas and electricity you use

To get an accurate quote for gas and electricity costs, you need to provide your energy usage, usually in kilowatt hours (kWh) per year.

Your latest bill or online account should tell you how much you've used in the past month. Look for your annual energy statement or summary for your use over a year.

If you don’t know how much energy you will use – for example, if you've just moved into a new home – you can estimate your usage. Price comparison websites will often ask a few questions to estimate what you use, for example:

  • the number of people living in your home
  • the type of property
  • the number of rooms.

Find out more about estimated energy-use figures.

Bear in mind that calculating your payments in this way will give a less accurate picture than your actual usage. So a few months into your contract, your payments could change to reflect how much gas and electricity you're actually using in practice.

Your payment details

To pay by direct debit, you will need to provide your bank details upfront (sometimes credit card details are permitted).

Compare gas and electricity prices 

With all these details to hand, you’re ready to compare energy prices. The most popular way to switch is via a price comparison website. These show you a range of deals so you can compare costs. Our independent service, Which? Switch, shows all available energy deals on the market, regardless of whether it can switch you to them. So you’ll know whether the deal you pick is really the cheapest.

Some price comparison websites (including Which? Switch) have a phone switching service. You can also check energy companies’ websites, phone your existing energy firm or use an online autoswitching service.

Once you've entered your details into the price comparison website, you’ll see a range of tariffs, usually in price order. There are various types of tariff to choose from, depending on what's important to you. Some of the most common ones include:

  • fixed tariff – the amount you pay per unit of gas or electricity is fixed for the term of your deal, often one or two years
  • variable tariff – the amount you pay per unit of gas and electricity will change whenever your energy company raises or lowers its prices. It must give you 30 days’ notice when it’s doing this, though
  • dual-fuel tariff – includes both gas and electricity, and is handy if you want to buy both fuels from one supplier
  • paperless tariff – also called online-only. You won’t get bills through the post, and will need to manage at least some of your account online. Some suppliers charge less for these, but not all.

Find out more about different types of tariffs and how to get the best energy deal.

Energy tariffs: what to check before you switch 

Once you’ve chosen your energy company and tariff, check the following to avoid any surprises later:

  • Does your tariff have exit fees? On some deals there's a charge if you want to leave before the end of your contract. Some firms charge around £30 per fuel. These only apply to fixed deals, and cannot be charged in the last 49 days of your tariff.
  • How much will your new deal cost per month? Check how this compares with your current deal, so there are no surprises to your bank account.
  • Is your direct debit fixed or variable? Fixed direct debit payments are the same each month, to balance out the cost of your energy during the year. Some companies have different fixed payments for summer and winter. Variable direct debit payments will vary each month to match what you use.
  • How will you receive your bills? Remember to check your online account or email if you won’t be getting them through the post.
  • Does your tariff require a smart meter? Some tariffs are only available to customers with smart meters, or if you agree to book an appointment to have one fitted.

How long does it take to switch energy supplier? 

It takes 16 days to switch your electricity supplier and 18 days to switch your gas supplier, on average, according to energy regulator Ofgem*.

That’s not including the 14-day cooling-off period the supplier must leave in case you want to change your mind before it begins the switch.

When we spoke to energy customers who had found switching energy supplier difficult**, the most common reason (cited by 40% of frustrated switchers) was that the communication from their old supplier was poor or confusing. The next most common reason (for 37%) was that the process was too slow.

If you’re keen for a quicker switch, choose a company signed up to the Energy Switch Guarantee. These companies guarantee to switch your energy supply within 21 days (including the cooling-off period).

Companies signed up are: Breeze, British Gas, Bulb, EDF Energy, Engie, Enstroga, Eon, Flow Energy, M&S Energy, Npower, Octopus Energy, Pure Planet, Scottish Power, Shell Energy, So Energy, and SSE. (correct October 2019).

They also guarantee to contact your old energy supplier to tell it you’re leaving, work with it to make sure you’re not charged twice, and take responsibility if there are any problems. 

Once you've switched, they promise to send you a final bill within six weeks, and refund you any money owed within 10 working days. Find out more about the Energy Switch Guarantee.

*(Ofgem April 2019.)

**(Survey: September 2018, GB, 7,429 energy customers.)

Will I get compensation if I have a problem switching? 

If something goes wrong when you switch energy supplier, you may be eligible for compensation.

Rules from regulator Ofgem state that energy firms must pay customers £30 if:

  • you are switched without your permission
  • your credit balance is not refunded within 10 working days of your supplier sending your final bill.

The compensation is automatic, although you may need to tell your energy supplier about the problem.

Ofgem is also working on plans for automatic compensation if it takes longer than 21 days for a supplier to complete a switch, or if you don’t get a final bill within six weeks of switching. These rules aren’t in place yet, though – we’ll let you know when they are.

How to switch energy supplier as a tenant 

If you rent your home, you can still usually switch your energy supplier to get a cheaper deal.

If you pay your energy company directly for your gas and electricity, then you can choose your energy supplier. This is according to consumer protection law.

But if your landlord pays the energy company direct, they can choose the energy supplier. You might be in this situation if:

  • your energy costs are included in your rent
  • your landlord pays your energy supplier and reclaims the money from you
  • your landlord has taken responsibility for energy bills between tenancies.

Your tenancy agreement should state whether you or your landlord is responsible for paying the gas and electricity bills.

If your landlord pays the energy bills, you can ask them to change your supplier. But they don’t have to.

Your tenancy agreement might include a ‘default’ or preferred energy supplier that your landlord or estate agent has set up. You can ask to renegotiate this clause in your contract. Even if you can't change it, you're entitled to switch company as long as you pay the bills directly. You should inform your landlord or letting agent, though.

There may also be a clause that requires you to tell the landlord if you switch energy supplier, or return the account to the original energy supplier when you move out.

If you've just begun a new tenancy or haven’t switched energy supplier or tariff in a while, it’s likely you’re on the energy firm’s standard default or out-of-contract tariff. These are rarely the cheapest deals, so it’s worth comparing energy prices to see what you could save.

Which? Switch, our independent energy comparison site, can help you to find the best deal for you as a tenant, regardless of how long you’ll be renting for.

It lets you select the length of your tenancy, so you can compare energy prices based on how long you know you’ll be in your home, and take any exit fees into account.

If you have a prepayment meter and rent your home, you should still be able to switch. Find out whether a prepayment energy meter is right for you.

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