CostRunningWhen should I read the meter?
An estimated bill is not a mistake by the supplier. It is what happens when nobody sends a reading.
One thing off the bill each month
MonthlyOne appliance a month worth measuring or changing, and what it does to the yearly total. No tariff pitches, no prices — the numbers that stay true.
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How this works
What regular readings tell you
The point of a habit rather than a one-off reading.
| How often you read | What it gives you |
|---|---|
| Once | A number with nothing to compare it to |
| Monthly | Real consumption, and a bill you can check |
| Weekly | Enough resolution to spot a change |
| Before and after a change | The actual saving, not the estimated one |
Two readings a month apart give you a real monthly consumption figure — the only number that makes any calculation on this site checkable.
Frequently asked questions
Does a smart meter make this pointless?
For submitting readings, mostly yes. For understanding the bill, no: reading the meter yourself before and after a change is the only way to measure what that change did, and smart meter data is often a day behind and awkward to compare.
When in the month should I read it?
A day or two before the bill is issued, so the reading arrives in time to be used rather than being carried to the next one. The exact date matters less than reading on the same date each month.
What about gas?
Same habit, same day, different meter. This site calculates electricity only, but the reading discipline is identical and the two are usually billed together.