Estimated energy bills: your rights and how to get an accurate bill

Great Britain · Rules checked 24 October 2026 · Not legal advice

Estimated bills aren't against the rules, but suppliers have duties that limit how long they can rely on them. These are in SLC 21B of the supply licence.

What suppliers must do

• Use a reasonably accurate reading you provide in your next bill or statement (21B.1). If they think it's wrong, they must take reasonable steps to contact you for a new one (21B.2).
• Take all reasonable steps to get a meter reading at least once a year (21B.4).
• Make a bill or statement available at least twice a year, or quarterly if you ask (21B.5, not for prepayment or smart meters).
• Explain how a bill was worked out, in plain and intelligible language, if you ask (21B.7).
• Give you your billing and consumption history on request (21B.9), and not charge you for a bill (21B.8).

How to fix an estimated bill

1. Take a dated photo of the meter showing the reading and serial number.
2. Submit the reading and ask for a re-issued bill.
3. If it isn't used, write formally (letter 02 in the kit) quoting SLC 21B.
4. If estimates ran for over a year and you now get a big bill, check the 12-month rule.

Questions