Economy 7 calculator
Economy 7 only pays off if enough of your usage genuinely happens overnight. Enter your own rates and split to find out whether it does.
p/kWh
p/kWh
p/day
kWh a year
Share of your electricity used at night
p/kWh
- No registration
- No email required
- Instant calculation
- Latest official Ofgem data
An honest limitation
Ofgem's published cap figures do not break out separate day and night rates in the dataset we import, so this calculator needs your own rates from your bill. We would rather ask you for two numbers than benchmark you against a figure that does not exist.
Mistakes that change the answer
- Guessing the night share. Most households overestimate it badly — check a bill with separate registers.
- Forgetting that the off-peak window differs by meter and region, and can shift with the clocks.
- Running heating on the day rate because a timer was never set.
Common questions
Is Economy 7 worth it?
Generally only with storage heating, an EV charged overnight, or a similarly large night load. The calculator gives the threshold for your own rates.
What single rate would beat my Economy 7?
The blended figure the result shows. Any single-rate tariff below it is cheaper for your usage pattern.
See whether you could pay less
Your results above are based on official Ofgem figures and your own numbers. Switching is optional and nothing here changes what the calculation says.
Compare your tariff against anotherAffiliate disclosure — commercial links never change your results or the Ofgem figures we show.
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