Compare energy suppliers

These organisations have different jobs.

Energy supplier

The supplier offers the tariff, buys energy for customers, issues bills, collects payment, supports vulnerable customers and handles account or meter-reading problems.

Network operator

Electricity distribution network operators and gas distribution networks maintain the local infrastructure. They respond to power cuts, gas-network emergencies and some connection issues. The network company is determined by location, not chosen through a normal tariff switch.

Generator

Generators produce electricity. A supplier can buy electricity from generators or through wholesale markets without owning the power station.

Understanding the difference helps direct a problem to the right organisation.

Total annual cost

Use annual electricity and gas consumption from a recent bill. Calculate usage charges and standing charges for the same region and payment method.

Annual cost = unit rate × annual use + daily standing charge × 365

Then account separately for exit fees, one-off credit, time-of-use rates and contract length. Do not treat a temporary credit as a permanent reduction in the tariff.

Tariff type

Check whether the offer is fixed, standard variable, tracker, time-of-use, prepayment, EV, heat-pump or another specialist tariff. Understand what can change and when.

Customer service

Compare complaints, contact waiting time, billing and metering performance, accessible contact routes and support commitments. Citizens Advice publishes a domestic supplier customer-service comparison, while Ofgem publishes market and customer-service data.

Scores describe a measured period and can change. The comparison below shows the period, source and method so the figures can be checked and updated consistently.

Eligibility and equipment

Some tariffs require a smart meter, Direct Debit, a compatible EV or charger, a heat pump, solar panels or an existing relationship with the supplier. Confirm eligibility before calculating savings.

Exit terms

Fixed tariffs may charge an exit fee. Standard variable tariffs cannot. Domestic fixed-tariff customers normally enter an exit-fee-free switching window 49 days before the end date, or when renewal terms are sent if earlier.

Green and renewable claims

Read what the claim covers. A supplier may match electricity use with renewable certificates, contract directly with generators, invest in new generation or use a combination. These are different propositions and should not be presented as equivalent without explanation.

Use the same:

• annual electricity and gas consumption;
• region;
• payment method;
• meter arrangement;
• comparison period; and
• tax treatment.

Include:

• every unit rate and time band;
• standing charges;
• contract length;
• exit fees;
• one-off credits;
• eligibility conditions;
• smart-meter or equipment requirements; and
• what happens when the deal ends.

The monthly Direct Debit is not the tariff price. It is a payment amount based on forecast use, account balance and supplier calculations.

Use the whole-bill tariff calculator →

1. Find annual kWh use, current tariff, end date and exit fee.
2. Compare complete annual costs and service information.
3. Check eligibility and contract terms.
4. Agree the new tariff with the chosen supplier.
5. The new supplier manages the switch.
6. Take and retain meter readings on the completion date.
7. Check the old supplier’s final bill and credit refund.
8. Check the first bill from the new supplier against the agreed tariff.

Ofgem says household electricity or gas switches should complete within five working days. If the standard is missed, the new supplier must normally make an automatic compensation payment. Check the current Ofgem page for the amount and conditions; as of 23 September 2026, the stated payment is £40.

A consumer who changes their mind can normally cancel a switch within the 14-day cooling-off period.

Ofgem’s current guidance says a credit customer can still switch if the debt is less than 28 days old, with the outstanding amount added to the final bill. Debt older than 28 days normally needs to be repaid before switching.

Prepayment customers may be able to transfer debt under the Debt Assignment Protocol. The current threshold is up to £500 for gas and up to £500 for electricity, subject to the new supplier accepting the transfer.

Disputed bills and individual circumstances can be more complicated. Contact the supplier and Citizens Advice if a switch is blocked unexpectedly.

Price matters, but support matters when a bill, meter or payment goes wrong. Before switching, check whether the supplier offers the contact method needed and how its service has performed recently.

The Priority Services Register provides free additional support for eligible people who may need help because of age, health, disability or another vulnerable situation. Contact the supplier and local network operator; joining one register may not automatically add the household to every relevant register.

If a household is struggling to pay, contact the supplier early. Suppliers must consider ability to pay when agreeing a repayment arrangement and may offer other support.

Complain to the supplier first and keep dates, bills, meter readings, screenshots and copies of messages. State the outcome wanted and ask for a complaint reference.

Under the rules current on 23 September 2026, a domestic customer can take an unresolved complaint to the Energy Ombudsman after eight weeks or sooner after receiving a deadlock letter. The service is free to the consumer. Announced reforms may reduce this period, so the wording should be checked before every update.

Citizens Advice can provide independent help with supplier, debt and switching problems.

Ofgem’s Supplier of Last Resort process moves domestic customers to a replacement supplier. The gas or electricity supply is not cut off because the supplier has failed, and domestic credit balances are protected.

If this happens:

• take a meter reading and keep a photograph;
• download recent bills and account information if available;
• do not rush to switch before the replacement supplier explains the new account;
• follow current Ofgem advice before cancelling payments; and
• check the opening balance and tariff once the replacement supplier contacts you.

Customers can normally choose another supplier after the transfer is established.

• Have you used annual kWh rather than the Direct Debit?
• Are both unit rates and standing charges included?
• Is the tariff fixed, variable or time-of-use?
• What are the exit fees and end date?
• Does a credit disappear after the first year?
• Is a smart meter or particular device required?
• Does the customer-service evidence cover a recent stated period?
• Are accessible contact and vulnerability support available?
• What happens at the end of the contract?
• Is the comparison independent and does it cover the whole market?