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How to calculate your energy bills

How to calculate your energy bills

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Last updated: 02 July 2021

Are you paying above average for your energy? Let’s find out.  

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What is an energy consumption calculator?

An energy consumption calculator can help you work out exactly how much energy you’re using. By using national data for different types of households, it shows on average how much electricity and gas a property like yours should use.

Why is this helpful? Well, as it’s based on averages it shows you exactly that; whether you’re consuming more or less than similar households. But further to this, it shows average prices for unit rates of energy too, so you know what a standard bill looks like.

If you find you’re paying over the odds, run an energy comparison to see how much you could save if you switch supplier. 

Further still, why not read our guide to the average energy consumption for UK homes to see what you can do to bring down your usage.

How to use our energy cost calculator

To use our energy calculator, we first need some details about your home, such as property age and type, the number of bedrooms you have and which region you live in.

We’ll then show you the average UK energy usage of a household of your kind. But here’s the nifty thing: you can use the tool to tell us what unit rate you pay for energy, as well as your standing charges. Behind the scenes, our calculator then works out your energy costs.

In short, there really is no simpler way to know if you’ve got a cheap energy deal or are paying a premium for your supply. But do bear in mind, this is a base cost of energy – other charges that make up your bill such as VAT won’t be included.

Electricity cost calculator

An electricity cost calculator is a quick and simple way to find out exactly how much your electricity costs.

Electricity bills are measured in kilowatt hours, which is how much electricity an appliance would use if it were to run for an hour. You pay a unit rate per kwh of electricity you consume.

Every appliance has a wattage, which you can usually find in the handbook. Our calculator asks for the wattage of your appliances and how often you use them – that’s everything from boiling kettles to charging phones. If you’re unsure of a wattage, you can look at average figures to help.

Once you know your appliance consumption, pop this info into our calculator and tell us your electricity unit rate. We then do the hard maths and voila; you’ll see what your electricity costs (though again remember this won’t include any additional charges that make up your bill).

If you find this figure uncomfortably high, then it may be time to compare energy deals offered by other suppliers to find one better for your wallet.  

How are my energy bills calculated?

Your energy bill is calculated as follows:

unit rate x kwh of energy consumed

You’ll also pay a standing charge for each day of your bill. For electricity, the average UK standing charge is 22p per day; for gas it’s 26.5p per day. This gets included in your statement.

If you’re on a fixed-rate deal, your unit rate will always be the same. By contrast, variable-rate tariffs mean the unit rate paid for your energy fluctuates with wholesale costs, so you could find this figure changes between bills.

Lastly, you may have additional costs and charges on your bill, some of which are outlined below.

How to read your energy bill

Formats may differ between suppliers, but most energy bills should contain the following information:

  • Your consumption
  • Your standing charges
  • The payment period for the bill
  • Any applicable discounts
  • VAT
  • Whether your bill is an estimation or an accurate total
  • Wholesale price of energy
  • How you choose to pay
  • Your tariff
  • Your Meter Reference Number (MRN)

Probably the most essential nugget of information to clock is whether your bill is an estimation or an accurate figure, so you can prepare for any adjustments later on.

Suppliers must now also disclose what the wholesale price of energy is, so you can check you’re not being drastically overcharged. If there is any part of your bill that doesn’t seem transparent, contact your supplier.

What affects the price of energy?

The price of energy is affected by a multitude of factors. Wholesale prices of energy are influenced by anything from global politics, supply and demand, to even the weather. As an example, if a natural disaster temporarily halts the extraction of oil, resources are scarcer and so prices rise. A supplier will also have its own policies on what it charges for energy.

How to get cheaper energy

Indisputably, the best way to get cheap energy is to stay ahead of the market. You should frequently compare energy dealsc using a tool that scours available tariffs from a huge pool of providers, like ours.

Energy companies offer the most competitive rates to new customers, so switching suppliers when your contract ends ensures you’ll always get the best rates on the market. 


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Michael Quinn

Author: Michael Quinn

Michael is a dedicated author helping usave to write guides, blogs and news for the last four years. When not writing articles, you can usually find him at wine tasting events or having a political debate on the night tube.

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