Estimated business energy bills: why they happen and how to stop them

If your business energy bill is estimated, the supplier has billed you for energy it believes you used rather than what your meter shows. The fix is almost always the same: send an accurate meter reading, ask for the bill to be recalculated, and set up a way of supplying readings regularly.

Why bills end up estimated

Common causes include:

• Nobody supplied a reading and the supplier could not obtain one itself, for example because the meter is in a locked cellar or behind a shop counter.
• A smart or advanced meter that has stopped sending data, so the supplier falls back on estimates.
• A change of supplier or tenancy where the opening reading was wrong. The Energy Ombudsman published a case where an account was opened with an incorrect meter reading and produced an electricity bill of over £2,200; the supplier eventually rebilled on actual readings and cut the balance to £93.02, then wrote that off.
• A wrong meter point number on the account.

How to tell a bill is estimated

Look at the readings section of the bill. Estimated readings are normally flagged, often with an "E". Compare the closing reading with your meter today. If the meter shows a much higher or lower figure, the estimate is off. Our walkthrough on reading your business energy bill shows where to look.

What an estimate costs you: a worked example

Suppose a café really uses 1,200 kWh of electricity a month but the supplier estimates 800 kWh for six months, at an illustrative 28.4p/kWh (the Moneysupermarket October 2026 micro-business fixed average).

• Actual use: 1,200 x 6 = 7,200 kWh
• Billed use: 800 x 6 = 4,800 kWh
• Shortfall: 7,200 - 4,800 = 2,400 kWh
• Catch-up cost: 2,400 x £0.284 = £681.60, plus 20% VAT (£136.32) = £817.92

Six months of smaller bills turns into one large correction. The opposite can also happen: overestimates put you in credit, which is your money tied up; see business energy refunds and credits.

Step by step: correcting an estimated bill

1. Read your meter. Photograph the display and any serial number. Our guide to submitting a business meter reading covers gas, standard electricity and multi-rate meters.
2. Submit it. Use the supplier's online account, app, phone line or email, and keep a record of when and how you sent it.
3. Ask for a recalculation. Request a new bill using actual readings, and a breakdown showing how charges were worked out.
4. Check the new bill. The opening reading, rate and dates should all be right.
5. Adjust your direct debit. If payments were set from wrong figures, ask for them to be reset.

Diarise a reading on the same day every month. Even a quarterly habit makes large corrections far less likely.

Smart and half-hourly meters

An advanced or smart meter should send readings automatically, which removes estimating. If yours is not reporting, read it manually and tell the supplier it needs fixing. Larger sites may sit on half-hourly metering, where consumption is recorded every half hour and estimating is far less common. Industry reform (market-wide half-hourly settlement) is moving more meters onto half-hourly settlement, and the government says that from 1 September 2027 new fixed-term non-domestic contracts must include a smart or advanced meter term.

How far back can a supplier correct a bill?

If a catch-up bill covers a long period, the 12-month back-billing limit may matter, but it covers only domestic and microbusiness customers. Check where you stand in business energy back billing. Not sure of your size? See what is a microbusiness for energy.

If the supplier will not fix it

1. Complain in writing to the supplier and keep copies.
2. Wait up to 8 weeks for a resolution, or until you receive a deadlock letter.
3. Take it to the Energy Ombudsman, which handles complaints from micro and small businesses. Do this within 12 months of the deadlock letter.

More detail is in energy disputes and the Ombudsman.

Questions to ask your supplier

• How was this estimate worked out, and from which past readings?
• When was the last actual reading recorded?
• Can you show the opening reading on this account and where it came from?
• If my meter is smart, why is it not reporting?
• Will you reset my direct debit once the bill is corrected?

Seasonal and part-year businesses

If you close for months at a time, an estimate based on last year's pattern may be wrong in both directions. A holiday let or seasonal cafe can end up with big winter debts or summer credit. Submitting a reading at opening and closing dates keeps the account honest. The standing charge keeps running while you are closed, so a quiet month still carries a bill.

When you take over premises

Take readings on the day you move in, photograph them and send them straight to the supplier. If you do not, the opening reading may be estimated and the account can start with a wrong figure, as in the Ombudsman case above. Our guide to setting up energy for a new business has a moving-in checklist.

Keep copies of every reading you send and the confirmation. If a supplier later says it never received them, the confirmation is your proof.

A simple monthly routine

Pick one person to own the task, so it does not depend on whoever happens to be in. Give them a short list: the meter locations, a key if the cupboard is locked, the supplier login and a shared folder for photos. Ask them to read both fuels, photograph the displays, send the figures and save the confirmation. Once the habit is set, a reading takes minutes, and your bills stay close to what you really use. If you have several sites, rotate responsibility so that a holiday does not leave one meter unread for a quarter. Review the first bill after a routine starts: the readings should now be marked as actual, and any earlier estimate should have been trued up.

If you pay by direct debit, check that the monthly figure matches your actual run rate once the corrected bill arrives. A direct debit built on an old estimate will keep producing credit or debt even after the readings are right.

Next steps

• Read the meter today and send it.
• Ask the supplier how often it plans to obtain reads.
• Dispute any unexplained charges in writing and keep copies.