What does “estimated” mean on my bill?
Last updated: 6 September 2026 · Figures from the current Ofgem price cap
An estimated reading means nobody read your meter. Your supplier guessed what you used, based on your past bills and the time of year, and charged you for that. It is a placeholder, not a measurement. The bill is still legally due, but you can replace the guess with a real reading and have it corrected.
How to spot one
Find the meter readings section and look for a single letter beside each number. That letter tells you where the reading came from.
| Code | What it means |
|---|---|
| E | Estimated by your supplier |
| A | Actual reading, taken by the supplier |
| C | Customer reading, the one you sent in |
| S | Smart meter reading, sent automatically |
Labels vary slightly by supplier. Some spell out “estimated” in full instead of using a code.
Why suppliers estimate
Usually because nobody could get to the meter. The meter reader found the house empty, the meter sits in a locked cupboard or cellar, or you have a traditional meter and haven’t sent a reading recently. Rather than skip the bill, the supplier fills the gap with a projection from your history.
A smart meter sends readings on its own, which is why estimates are rarer on those accounts. Even then a smart meter that has lost signal, or one left in dumb mode after you switched supplier, falls back to estimates without saying so on the front page.
What goes wrong
An estimate that runs high means you are lending your supplier money you did not owe. An estimate that runs low is worse, because the shortfall is still yours to pay and it grows quietly until someone reads the meter. Households that cut their usage often keep getting billed at the old level, since the estimate is built from what they used to do.
The knock-on effect lands on your monthly payment. Suppliers set direct debits from projected annual usage, so a run of high estimates pushes your payment up for a year on the strength of a number nobody checked.
It also distorts any comparison you try to make. Your unit rate is a real, printed price at around 26.11p per kWh, but the usage it multiplies is guesswork. Working out whether your bill is normal starts with a genuine reading.
Why the date matters right now
The current price cap runs to 30 September 2026, and new rates take over on 1 October. When prices change part-way through a billing period, your supplier splits the usage across the old rate and the new one.
Without a real reading on the changeover date, that split is an estimate as well. Sending a reading in the last few days of September pins down how much of your energy is charged at the older rate, which is worth doing whichever way the cap moves.
How to put it right
Send a current reading through your supplier’s app, website or phone line. They must reissue the bill against the figure you give them. If the estimate was too high, the difference comes back as credit on your account or a refund you can ask for.
Photograph the meter with the date visible when you send it. That photo settles most disputes on its own, and it costs you nothing.
If a big catch-up bill arrives
Years of low estimates ending in one real reading produces a bill that can run to hundreds or thousands of pounds. There is a limit on this. Ofgem’s back-billing rule stops a supplier charging you for energy used more than 12 months ago if they never billed you correctly for it at the time.
If a catch-up bill reaches further back than that, say so in writing and name the rule. Citizens Advice will help you put the complaint together, and the Energy Ombudsman can take it on if your supplier refuses.
Common questions
What does E mean on my energy bill?
An E beside a meter reading means it's estimated: worked out from your past usage rather than read off the meter. An A is an actual reading taken by the supplier, a C is one you sent in yourself, and an S comes automatically from a smart meter.
Do I have to pay a bill based on an estimated reading?
The bill is legally due, but it isn't final. Send a current reading and your supplier must reissue it against the real figure. If the estimate ran high, the difference comes back to you as credit or a refund.
Can my supplier bill me for old energy they underestimated?
Only up to a point. Ofgem's back-billing rule stops a supplier charging for energy used more than 12 months ago if they never billed you correctly at the time. Quote it if you get a catch-up bill covering several years.
Why does an estimated reading matter when the price cap changes?
When rates change mid-period your supplier splits your usage across the old and new prices. With no real reading on the changeover date, that split is estimated too. A reading close to the date fixes how much is charged at the older rate.
Check the rest of the bill while you're here
Send your supplier a reading first, then upload the bill. We'll pull out your rates and usage and show you how they compare to the July 2026 cap. On an estimated bill the comparison is only as good as the estimate, so a real reading makes it worth having. About 30 seconds.
Check my billYour bill is deleted as soon as we’ve read it.