What are the red flags on an energy bill or tariff?

Payments, readings and old charges

A Direct Debit rises sharply or your account shows a large credit: ask for the usage forecast, tariff, readings and balance calculation in writing. Provide actual readings and challenge an amount that does not match your account history. If there is genuine excess credit, request a fair refund; keep enough for expected bills if you prefer a buffer.

Repeated estimated bills or an unexpectedly high bill: photograph the meter, submit a dated reading, and ask the supplier to rebill using actual readings where possible. Check that the reading is for the right meter and that the meter serial number matches your bill. Do not ignore bills while a correction is investigated.

A charge for energy used long ago: ask for a date-by-date breakdown and why it was not billed earlier. Domestic back-billing rules often prevent recovery for periods over 12 months where supplier fault caused the delay, but exceptions apply. Do not assume the rule applies without checking the facts and relevant guidance.

Tariff changes and sales pressure

Your fixed tariff is ending: note the end date and ask what tariff you will move to, if any. Compare the new unit rates and standing charges with other available options using your annual kWh; do not judge by monthly payment alone.

An exit fee appears when you want to leave: check the tariff terms, the dates and whether the fee applies to your circumstances. Ask the supplier to explain it before switching; some tariffs have no exit fee and rules may affect when one can be charged.

A cold caller or doorstep seller pressures you to switch, asks for a bill, or wants account details immediately: do not share passwords, one-time codes or payment details under pressure. Ask for written information, independently contact the supplier using its official number, and take time to compare. You can end an unsolicited sales conversation.

Prepayment concerns and how to escalate

A prepayment meter is running out and you cannot top up, or you are unsure about a proposed meter change: contact your supplier promptly and explain any vulnerability, disability, health need or difficulty paying. Ask about emergency and friendly credit, affordable repayment, support and the rules for your specific situation. Keep records; do not tamper with a meter.

If the supplier does not resolve a problem, make a formal complaint and keep the reference number. Suppliers have up to eight weeks to resolve a complaint, or can issue a deadlock letter sooner; after that, eligible cases can go to the Energy Ombudsman. Procedures and eligibility vary, particularly in Northern Ireland.

Scope

This guidance is for domestic consumers. Ofgem rules discussed here generally concern Great Britain; Northern Ireland has separate energy arrangements. Check current official guidance for your location and circumstances.

Good to know

Should I cancel a Direct Debit if my bill looks wrong?

First contact the supplier, submit a reading and ask it to explain the amount. If you change a payment instruction, understand how you will pay ongoing charges and avoid leaving an unexplained balance.

What should I do about estimated bills?

Take and submit an actual reading, keep a dated photo if useful, and ask your supplier to recalculate the bill.

Can a supplier always charge a fee if I leave a fix?

Not always. Check the tariff contract, end date and applicable rules; ask the supplier to explain any fee.

When can I go to the Energy Ombudsman?

Usually when eight weeks have passed since your complaint or you have received a deadlock letter, and the case meets the Ombudsman's eligibility rules.

Sources

• Citizens Advice: complain about an energy company
• Citizens Advice: energy back-billing
• Ofgem: energy advice for households
• Energy Ombudsman