Estimated vs Actual Gas Readings — Your Rights

Estimated vs actual gas readings is one of the most common billing disputes in the UK. If your supplier has been guessing your usage instead of using real readings — you have rights, and you can challenge it. Here’s everything you need to know.

What is an estimated reading?

An estimated reading is when your energy supplier calculates your bill based on predicted usage rather than a real meter reading. It’s shown on your bill with an “E” next to the figure.

Suppliers are allowed to estimate — but only within limits. If your smart meter isn’t communicating automatically and you haven’t submitted a manual reading, your supplier will estimate based on your historical usage patterns.

What is an actual reading?

An actual reading is a real figure taken directly from your meter — either automatically via your smart meter’s communication system, submitted manually by you, or taken in person by an engineer.

Actual readings are always more accurate than estimates and should be the basis of your bill wherever possible.

Why estimated readings cause problems

Estimates are based on averages and historical patterns. They don’t account for:

Changes in your household size or usage habits
Moving into a property with different usage history
Seasonal variations being applied incorrectly
A meter that was replaced or reset

When a real reading eventually comes through after a long period of estimates, it can trigger a large correction — either a sudden bill increase or an unexpected credit. Both can feel shocking if you weren’t expecting them.

Your rights around estimated readings

Under Ofgem rules, energy suppliers in the UK must:

Use actual readings wherever possible
Accept manual readings you submit yourself
Recalculate your bill if you provide an actual reading that differs from their estimate
Not backdate estimated charges beyond 12 months in most circumstances

The 12-month rule is important. If your supplier has been estimating for longer than a year and suddenly presents you with a large back-bill, you may be protected under Ofgem’s back-billing rules — meaning you don’t have to pay charges older than 12 months if the error was the supplier’s fault.

What to do if you’ve been billed on estimates

Take these steps in order:

Take a manual reading from your meter right now and note the date and time
Submit it to your supplier immediately via their app or website
Ask them to recalculate your bill based on the actual reading
Check your bill history for how long estimates have been used
If the back-bill covers more than 12 months, reference Ofgem’s back-billing protection

Check what your bill should actually be — Bill Checker →

What if your supplier won’t budge?

If you’ve submitted an actual reading and your supplier is still billing you incorrectly, or refusing to apply back-billing protection, you have the right to raise a formal complaint.

A written complaint triggers your supplier’s official complaints process, which has regulatory deadlines they must meet. If they fail to resolve it within eight weeks, you can escalate to the Energy Ombudsman — for free.

Generate a formal complaint letter in minutes →

How to prevent estimated readings in future

Check your smart meter is in smart mode and communicating with your supplier
Submit manual readings regularly if your smart meter isn’t communicating
Check each bill for an “E” next to your readings

→ Smart gas meter not sending readings — what’s happening

Not sure where you stand?

Run a free Health Check and we’ll help you work out what’s happening with your meter and what to do next.

Start your free Health Check →

Related help:

All advice on SmartMeterHelp is independent. We’re not affiliated with any energy supplier.