Check whether you could pay less for energy
Work out whether your bill is big because of how much you use or because of what you pay per unit — then what you can change for nothing before spending anything.
Check if you could pay lessFree, no account, and nothing you enter leaves your browser. You need your annual usage and your rates — both are on a recent bill.
What is it actually costing?
Start here if you have a bill in front of you. These work from your own rates and meter readings, so the answer is checkable against the bill rather than a national average.
- Electricity cost
You want to know what your electricity actually costs, and whether the bill is right.
- Gas cost
Your gas bill is in kWh but your meter reads in cubic metres or hundreds of cubic feet.
Where is it going?
A bill tells you the total. These narrow it down to the parts you can do something about — and the part you cannot.
- Base load
Something is using electricity around the clock and you do not know what.
- Appliance cost
You want to know what one appliance costs to run, and whether standby matters.
- Standing charge
You use very little energy but the bill never seems to fall.
- Usage estimator
You do not know your usage and need a starting figure before anything else works.
Paying less for the same energy
The pay-less check is the dominant action at the top of this page; it is repeated here so the sequence reads properly. Free changes still come before switching, because a cheaper tariff on the same usage saves less than most people expect and takes effort to arrange.
- Pay less check
Your energy costs more than you would like and you do not know whether that is how much you use or what you pay for it.
- Tariff check
You have two tariffs in front of you and cannot tell which is actually cheaper.
How energy bills work
- How to calculate an electricity bill
The two-part sum every supplier uses, where to find each figure, and why your answer will be a few percent out.
- How to calculate a gas bill from meter readings
Converting cubic metres or hundreds of cubic feet into kWh using the formula on your own bill, and why the calorific value matters.
- What is an energy standing charge?
The fixed daily amount you pay for being connected, why it cannot be avoided, and when a lower one is actually worse.
- Which appliances use the most electricity?
Ranked by what they actually cost a year rather than by how powerful they are — the two are not the same.
- Why is my electricity bill so high?
The causes in the order they are worth checking, starting with the ones that are free to rule out.
- Why is my gas bill so high?
Why gas bills move so much between seasons, and what to check before assuming something is wrong.
- Fixed versus variable energy tariffs
What each one actually commits you to, and why "cheaper" depends on a question nobody can answer in advance.
- How to read an electricity meter
Digital, dial and Economy 7 meters, and which digits to write down on each.
- How to read a gas meter
Metric and imperial meters, which digits count, and how to tell which type you have.
- How to find your overnight base load
Two meter readings, a division, and the most informative measurement you can take about your electricity — for nothing.
What these tools do not do
We do not connect to your supplier. Every figure here comes from what you type in, off your own bill or meter.
We do not list suppliers or tariffs, and we do not switch anything for you. The tariff comparison works on two tariffs you enter yourself.
We cannot tell you whether your unit rate is competitive. That needs live supplier prices from a comparison service accredited under Ofgem’s Confidence Code, and we have not got one yet. What we can tell you is whether your usage or your rates is the part with room in it — which is the question worth answering first either way.
We do not store anything you enter. Nothing leaves your browser.