How to switch energy supplier

Britain's energy market separates the supply of energy from its delivery. Your supplier buys energy and bills you. A regional distribution network operator owns and maintains the cables and pipes that reach your property, and you do not choose them — they are determined by where you live. Switching supplier does not change the network operator, the physical infrastructure, or who attends a gas leak or a power cut.

This has practical consequences. If your electricity keeps cutting out, if a street light is down, if you smell gas, if your supply needs upgrading from single to three phase, the supplier is not the right body to call. Those are network operator matters, and Ofgem publishes a tool to identify who yours is. The gas emergency number and the power cut number are national and do not change with your supplier.

A switch also does not change your meter. The physical meter stays where it is, and the new supplier takes over the readings. The exception is where you specifically request a smart meter installation, which is a separate arrangement with your new supplier and not part of the switch.

Nor does it change the quality of the energy. There is no separate stream of greener electrons for a green tariff. A renewable tariff is a contractual and certificate-based arrangement — the supplier buys Renewable Energy Guarantees of Origin certificates matching your consumption — not a different physical supply. That is a reason to look carefully at what a green tariff actually commits the supplier to, not a reason to dismiss it.

What switching does change is the unit rate, the daily standing charge, the payment terms, the billing quality and the customer service. Those are worth real money, and the standing charge in particular is worth attention if you use very little energy, because it is payable whether you use anything or not.

One more thing does not travel with you automatically: your position on your supplier's Priority Services Register. That register is per supplier, so if you are on it for reasons of age, disability, illness or having young children, you need to re-register with the new supplier. Doing so takes minutes and is free.

Find your annual consumption in kilowatt hours. It appears on your annual statement and on most bills, usually near the back, shown separately for gas and electricity. If you cannot find it, your supplier must provide it, and a smart meter account will show it in the app. Everything else follows from this number.

Take a meter reading on the day you start the process and photograph it with the date visible. You will need it at the switch, and a photographed reading is the evidence that settles a dispute about the final bill.

Note your current tariff name, whether it is fixed or variable, the end date if it is fixed, and whether an exit fee applies. All of this is on your bill or in your online account. A tariff nearing its end date is the moment where switching is easiest, because exit fees cannot be charged in the final stretch of a fixed deal.

Note how you pay. Monthly direct debit is generally the cheapest payment method, with payment on receipt of bill costing more and prepayment sitting under its own cap arrangements. If you are considering changing payment method as well as supplier, price both changes separately so you can see which one is doing the work.

Check your account balance. Direct debit accounts routinely build up credit over summer, and that credit is your money. You can ask for it back at any point, and the old supplier must return any remaining credit after issuing a final bill following a switch. Knowing the balance before you switch means you notice if the refund does not arrive.

Compare using an Ofgem-accredited comparison site, and enter your actual kilowatt hours rather than accepting the default household profile. Compare the estimated annual cost, not the unit rate alone, because a low unit rate paired with a high standing charge can be worse for a low-usage household and better for a high-usage one.

You do not contact your existing supplier. The new supplier runs the switch, notifies the old one, and the old supply contract ends automatically. Telling your old supplier you are leaving is unnecessary and occasionally counterproductive, because it invites a retention call rather than completing anything.

A 14-day cooling-off period starts when you agree the new contract. During it you can cancel without penalty for any reason. You can waive it to switch faster, but there is rarely a good reason to.

Once the cooling-off period ends, the switch must complete within five working days. You will be asked for a meter reading around the switch date; give it promptly, because a missing reading forces both suppliers to estimate and estimates are the origin of most switch disputes.

Your old supplier issues a final bill, normally within six weeks. Check it against your photographed reading. If you are in credit, the balance is refunded; if you owe, it is payable. If the final bill uses an estimate that does not match your reading, challenge it with the photograph.

The new supplier sets up your account, confirms your tariff and sets your direct debit. Check the direct debit amount against your actual consumption rather than accepting it — an over-set direct debit builds credit balances, and an under-set one produces a shortfall later.

Re-register for the Priority Services Register with the new supplier if it applies to you, and check whether the Warm Home Discount is affected. Eligibility for that scheme is assessed against the supplier you are with at a specific point in the year, so a switch at the wrong moment, or to a supplier not participating, can cost you the rebate for that year.

Ofgem operates Guaranteed Standards of Performance for switching. These are not goodwill payments. Where a switch takes longer than the required period, where a customer is switched without their consent — an erroneous transfer — or where a final credit balance is not refunded within the required time, compensation is payable automatically, without you having to claim.

In practice the automatic part often does not happen, which is why it is worth knowing the standards exist. If a switch overruns, if you find yourself billed by a supplier you never agreed to, or if a credit refund has not arrived weeks after the final bill, raise it as a complaint and cite the Guaranteed Standards.

An erroneous transfer — being switched without consent, usually through an address or meter identifier mix-up — has its own process. The two suppliers must sort it out between them and return you to your original supplier on your original terms. You should not be worse off, and you should not be paying two suppliers for the same energy.

If your supplier ceases trading, do not switch and do not panic. Ofgem appoints a Supplier of Last Resort, your supply continues without interruption, and any credit balance is protected and transferred. Trying to switch during the appointment process complicates the transfer. Take a meter reading immediately, keep the old bills, and wait to be contacted by the new supplier — then switch away afterwards if the tariff you are moved onto does not suit.

For anything the supplier does not fix, the escalation path is fixed. Complain to the supplier first, in writing. If it is not resolved after eight weeks, or if the supplier issues a deadlock letter earlier, you can take it to the Energy Ombudsman free of charge. The ombudsman's decision binds the supplier if you accept it, and it can order compensation as well as correction of the account.

Keep every reading, every bill and every reference number until a dispute is closed. In energy complaints the party with the dated meter photograph generally wins.

Debt blocks a switch. If you owe your current supplier for energy billed more than 28 days ago, the supplier can object to the transfer and normally will. The route out is to clear the debt or agree a repayment plan, not to keep trying. Prepayment customers are treated differently: the Debt Assignment Protocol allows a prepayment meter customer to move to a new supplier taking a capped amount of debt with them, which is a genuinely useful mechanism and is not well publicised.

Exit fees apply on fixed tariffs and are charged per fuel. They cannot be charged if you switch in the final stretch of the fix — the switching window at the end of a fixed contract — so the cheapest time to leave a fixed deal is in its last weeks. If you want to leave earlier, price the exit fee against the saving rather than assuming it kills the deal.

If you are on a restricted meter — Economy 7, Economy 10, a total heating total control meter, or an older radio teleswitch arrangement — the number of suppliers who can serve you is smaller, and comparison is harder because your saving depends on how much of your consumption falls in the cheap period. Check your day and night split before comparing rather than after.

If you rent, check who holds the supply contract. Where you pay the supplier directly you can switch, and a tenancy clause purporting to forbid it is generally unenforceable, though you may be required to return the property to its original supplier at the end. Where the landlord holds the contract and recharges you, you cannot switch — but the landlord cannot charge you more than they paid plus a reasonable administration amount under the maximum resale price rules.

If you are struggling to pay, switching is usually not the first move. Suppliers must offer affordable payment plans, and the schemes that make the biggest difference — the Warm Home Discount, hardship funds, the Priority Services Register, and energy efficiency grants — are attached to your circumstances rather than your tariff. Fix the debt position first, then switch once the account is clear.

Finally, a switch is not a fix for a wrong bill. If your bill is wrong because of a faulty meter, a misread meter or a back-billed catch-up demand, resolve that with the current supplier before leaving, because chasing an old supplier over a closed account is materially harder than chasing a live one.

Moving into a new property is not a switch. You inherit whatever supplier serves the address, on their deemed contract rates, which are usually among their more expensive. You are liable from the moment you take responsibility for the property, and you become a customer of that supplier automatically without signing anything.

On the day you move in, take meter readings for gas and electricity and photograph them. Find out who the supplier is — Ofgem publishes a tool for exactly this, and if you cannot identify the electricity supplier the meter point identifier can be traced through the network operator. Contact the supplier, give the reading, and open an account in your name.

Only then consider switching. You are free to switch immediately; the deemed contract has no exit fee. But do it in that order, because switching before you have opened an account at the address is the reliable way to end up with two suppliers claiming the same meter.

On the way out of your old property, take final readings, give them to your supplier with the move-out date, and give a forwarding address for the final bill or refund. A closing balance chased to an address you no longer live at is a common source of credit files being marked for sums people never knew they owed.

If the property has a prepayment meter you did not choose, you can ask to have it replaced with a credit meter. Suppliers must consider the request, and rules on installing prepayment meters without consent were tightened substantially after the practice was suspended in 2023.

Where the property has been empty, expect an estimated opening balance that bears no relation to reality. The dated photograph of the meter on move-in day is what corrects it.