Business energy complaints and the Energy Ombudsman

If a bill is wrong, a meter is faulty or a contract was not what you were promised, you have a clear route to get it looked at. This guide covers the order of steps, who the Energy Ombudsman can help and how to build a case that gets results.

The short version

1. Complain to the supplier (or broker) and keep a written record.
2. Wait up to 8 weeks, or ask for a deadlock letter if they will not resolve it sooner.
3. Take the complaint to the Energy Ombudsman, normally within 12 months of the deadlock letter.

Who can use the Energy Ombudsman?

The Energy Ombudsman covers households, microbusinesses and small businesses. Small businesses were added on 19 December 2024. It also handles complaints about brokers that belong to its broker scheme. The size tests are:

Size	Test (any one)
Microbusiness	Fewer than 10 staff and turnover or balance sheet of no more than 2 million euros; or under 100,000 kWh electricity; or under 293,000 kWh gas a year
Small business	Fewer than 50 staff and turnover up to £6.5m or balance sheet up to £5m; or up to 200,000 kWh electricity; or up to 500,000 kWh gas a year

The usage tests apply to the fuel you are complaining about, so a company can be eligible for an electricity complaint and not a gas one. See who can use the Ombudsman and microbusiness definitions. Larger businesses are outside the scheme and may need to use solicitors or other routes.

Step 1: Complain to your supplier

Citizens Advice's guidance says to raise the issue straight away. Then:

• Say what the problem is and what you want done.
• Note the date, time and name of whoever you speak to.
• Follow up calls with an email so there is a written record, and include your account number.
• Gather evidence: photos of a faulty meter, bills that look wrong, emails and letters.
• Use the supplier's formal complaints process, usually on its website. Writing is better than phone-only.

Common supplier complaints include a meter or supply fault that is not being fixed, repeated incorrect billing and disputed charges. See disputing a high bill, backbilling and faulty meters.

Step 2: The 8-week rule and deadlock letters

The Ombudsman normally wants the supplier to have had a chance to put things right. You can go to it when either:

• 8 weeks have passed since you started the complaint with the supplier and it is unresolved; or
• the supplier has sent a deadlock letter (a final response saying you cannot agree).

With a deadlock letter you can go to the Ombudsman straight away. See how long before you can go to the Ombudsman.

Worked timeline

• 3 February 2027: you make a formal written complaint.
• 3 February + 56 days (8 weeks) = 31 March 2027: if unresolved, you can apply to the Ombudsman.
• If the supplier sends a deadlock letter on 10 March 2027, you can apply from that day, and have until 10 March 2028 to do so.

Do not sit on a deadlock letter. Citizens Advice says to complain to the Ombudsman as early as possible, and without a deadlock letter you may still be able to complain after a year, but only depending on your case.

Step 3: Go to the Energy Ombudsman

The Ombudsman is free to use. It looks at both sides, asks for evidence and can recommend or direct remedies, such as correcting a bill, an apology or compensation. Prepare:

1. A short timeline of events.
2. Copies of bills, meter readings and correspondence.
3. Your complaint reference number and the supplier's final response if you have one.
4. A clear statement of the outcome you want.

Our guide on complaining about a broker covers that route. The Ombudsman says the maximum award for non-domestic supply disputes rose to £20,000 for new cases from 19 December 2024, while broker disputes stay capped at £10,000. Check the live limits when you apply.

Broker disputes

If a broker is paid by your supplier it must belong to a qualifying dispute scheme. Citizens Advice names the Energy Ombudsman, the Utilities Intermediaries Association (UIA) and the Dispute Resolution Ombudsman. If the broker is not registered with one of them you cannot use those schemes, so check before you start. Rules differ slightly: the UIA lets you go to it after 15 working days or if you are unhappy with the broker's response. See broker mis-selling.

Pending changes

In October 2025 the government proposed making Ombudsman decisions binding and cutting the wait before escalation from 8 weeks to 4. Its June 2026 consultation response settled on 6 weeks instead, for households and eligible small businesses, to be brought in by Ofgem and the Ombudsman as soon as reasonably possible and no later than Royal Assent of the planned Energy Independence Bill. Stronger powers to enforce decisions need new legislation. No start date had been set when we checked, so use the 8-week rule unless the Ombudsman tells you otherwise.

Other help

• Citizens Advice provides free advice to micro and small businesses, and suppliers must signpost you to it. Its consumer helpline is 0808 223 1133, according to the Citizens Advice website.
• Payment worries: if you are struggling to pay while a dispute continues, tell your supplier. See can't pay your business energy bills.

What a good complaint looks like

Keep it short and factual. Name the account and meter, set out what happened in date order, state the financial effect and say what you want. For example: "Bills from March to June 2026 are based on estimated readings. I sent actual readings on 4 April and 2 May. Please correct the bills and refund the overpayment of £X." Attach evidence and ask for a written reply within a stated time.

While the complaint is running

• Pay any undisputed part of the bill and tell the supplier which part you are disputing, to reduce the risk of late charges or debt action. See late payment charges.
• Keep sending meter readings so later bills are accurate.
• Do not switch supplier without checking whether the dispute will follow you; the old supplier's final bill can still be disputed.

Next steps

• Write to your supplier today if you have an open problem, and diarise the 8-week date.
• Check your size against the table above.
• Gather your evidence in one folder.