What is the Energy Switch Guarantee?

What is the Energy Switch Guarantee?

The Energy Switch Guarantee started in 2016 as a voluntary promise made by a group of UK energy suppliers. The goal was to make changing your gas and electricity provider simple, fast, and safe. Before this, switching could take weeks, and many households worried about being double-charged or losing their power supply during the handover.

Today, you do not need to worry about whether a supplier has signed up to the voluntary guarantee. The independent energy regulator, Ofgem, has taken the core ideas of the Energy Switch Guarantee and turned them into strict rules that every licensed supplier in Great Britain must follow.

These rules mean that switching is now legally required to be fast and hassle-free. If a supplier fails to meet these standards, they must pay you compensation. This guide explains exactly how the switching rules protect you, how long the process takes, and what happens if things go wrong.

How the switching process works today

The most important rule of the switching process is that the customer should not have to do the hard work. In the past, people often thought they had to call their old supplier to cancel their contract, which led to long wait times and pushy sales tactics. Your new supplier normally handles the switching process for you.^[1]

There is absolutely no risk of a power cut when you change supplier. Every energy company in Great Britain uses the exact same physical pipes for gas and the same network of wires for electricity. The only thing that changes is which company handles your customer service and sends you the bill. Nobody needs to visit your home, and nothing changes outside or inside your property.

Switching times and the cooling-off period

Under the original voluntary guarantee, suppliers promised to complete a switch within 21 days. Ofgem has since introduced the Faster Switching Programme, which legally reduced this timeframe. Today, an energy switch in Great Britain is usually completed within just five working days.

By law, you also get a 14-day cooling-off period when you sign up for a new energy contract. This gives you the right to change your mind and cancel the switch without paying any penalty or exit fee.

Because a switch can happen before the 14-day cooling-off period ends, you can still cancel after it has completed. The new supplier must cancel the contract without charging a termination fee, explain your options and temporarily continue supply while you choose a supplier. You must pay for the energy you use.

If you prefer, you can ask the new supplier to wait until the 14-day cooling-off period is completely over before they start the five-day switching process. Most people choose the faster option so they can start saving money on a cheaper rate straight away.

Final bills, refunds, and avoiding double charges

A major fear for many households is being charged by two different companies for the same energy. The switching rules are designed to make this impossible. The process relies on a single handover meter reading.

When you give your new supplier a meter reading on the day of the switch, they send that exact same reading to your old supplier. Your old supplier uses it to close your account, and your new supplier uses it to open your new account. This clear line means there is no overlap in billing.

Once the switch happens, Ofgem rules set strict deadlines for your old supplier to tie up loose ends:

You do not have to ask for this refund. The rules state that the supplier must process it automatically. If you cancelled your Direct Debit before they sent the refund, they must send you a cheque instead, which can take a little longer to arrive by post.

Automatic compensation if things go wrong

To make sure suppliers actually follow these rules, Ofgem enforces a system called the Guaranteed Standards of Performance (GSOP). If a supplier makes a mistake or misses a deadline during your switch, they must pay you compensation.

The standard compensation payment is £40. You are entitled to this £40 payment in several common situations:

An erroneous transfer usually happens when a supplier mixes up flat numbers or meter details and takes over your supply without your permission. If this happens, contact your old supplier. It has 21 working days to switch you back, and the new supplier must automatically pay you £40.

You do not need to fight for this compensation. Under Ofgem rules, the supplier must pay it to you automatically. If they fail to pay the compensation within 10 working days, they must pay you an extra £40 for the delay.

Can you switch if you are in debt?

A common myth is that you cannot switch energy supplier if you owe your current provider money. The reality depends on what type of meter you have and how long you have owed the money.

If you pay by Direct Debit or pay when you get a bill (a standard credit meter), your supplier can block your switch if you have been in debt to them for more than 28 days. If the debt is recent — for example, from a bill that arrived two weeks ago — they cannot stop you from leaving. If you are blocked, you will need to pay off the debt before you can move to a new supplier.

If you have a prepayment meter, the rules are much more flexible. You can switch to a new supplier even if you are in debt, as long as you owe £500 or less per fuel (up to £500 for gas and up to £500 for electricity). This is done through a system called the Debt Assignment Protocol.

When you switch, your debt moves with you to the new supplier. You simply continue paying it off through your top-ups at the same agreed rate. This rule exists so that households with debt are not trapped on expensive tariffs and can still shop around for a better deal.

Exit fees and the cost of switching

The switching process itself is entirely free. No supplier will ever charge you an admin fee to set up a new account or process a handover.

However, depending on your current tariff, you might have to pay an early exit fee to your old supplier. If you are on a standard variable tariff (the default tariff that most households fall onto when a contract ends), there are no exit fees. You are free to leave at any time.

If you are on a fixed-rate tariff that has not yet ended, your supplier may charge an exit fee if you leave early. This fee is usually around £25 to £75 per fuel. You can find out if you have an exit fee by checking your latest energy bill or logging into your online account.

Even if you have to pay an exit fee, switching can still save you money. For example, with the Ofgem price cap sitting at around £1,663 a year for a typical dual-fuel home in July 2026, standard variable tariffs remain expensive. If you find a cheap fixed deal, the savings on your monthly bills over the next year might easily cover the one-off cost of the exit fee. It is always worth doing the maths before you decide.

Ofgem rules state that if your fixed tariff is within 49 days of its end date, your supplier cannot charge you an exit fee. You can switch away freely during this final window.

Who is covered by these rules?

The switching rules and Ofgem regulations apply to domestic energy customers across Great Britain (England, Scotland, and Wales). Northern Ireland has a separate energy market with its own regulator and different switching rules.

Historically, households living in flats with communal heating systems (heat networks) did not have the same protections as standard gas and electricity customers. However, as of early 2026, Ofgem has become the official regulator for heat network operators as well. This means customers on these networks are beginning to see similar rules around fair pricing, transparent billing, and consumer protection applied to their heating supply.

If you rent your home and pay the energy supplier directly, you have the exact same right to switch as a homeowner. Your landlord cannot stop you from changing suppliers or force you to stay with a specific company, though it is polite to let them know if you change the meter type.