ENERGY COST CALCULATOR
Energy Cost Calculator UK
Use our free energy cost calculator to estimate how much electricity, gas or individual electrical appliances could be costing you.
Whether you want to check the running cost of an appliance at home or understand the energy cost of equipment used across a business, enter your usage information and energy rate to get a clearer view of your daily, weekly, monthly and annual costs.
Quick answer: Energy cost is mainly determined by how much energy you use and the price you pay per kilowatt-hour (kWh). For electrical appliances, wattage and running time determine consumption. For businesses, actual bills can also include standing charges, VAT, the Climate Change Levy and other contract-specific costs.
What does your appliance cost to run?
Select one or more common appliances, enter how long you use each one, and calculate your estimated annual electricity cost.
Select as many appliances as you need. Each appliance can have its own hours per day and quantity.
Selected appliances
Enter the daily usage for each appliance. Wattages are example values and can be edited to match your actual appliance.
Custom appliance
If your appliance is not listed above, enter its details here. Leave these fields blank if you are only using the common appliance selector.
Use a decimal for part of an hour, such as 0.5.
Appliance wattage and usage can vary significantly. For the most useful estimate, check the appliance label or manufacturer information and enter your actual usage where possible.
Estimate your business energy cost
Use annual consumption and current charges to create a practical starting estimate for your electricity and gas spend.
Electricity
Gas
Tax and savings assumptions
Calculator assumptions: electricity CCL = 0.775p/kWh and gas CCL = 0.689p/kWh.
Your result is an estimate. A tailored procurement review can test rates, contract timing and practical efficiency opportunities.
How Does the Energy Cost Calculator Work?
Energy suppliers normally charge for consumption in kilowatt-hours, usually written as kWh. One kilowatt-hour is the amount of energy used by a 1,000-watt appliance running for one hour.
- a 1,000W heater running for one hour uses 1 kWh
- a 500W appliance running for two hours also uses 1 kWh
- a 100W appliance running for ten hours uses 1 kWh
Once you know the number of kWh being used, you can multiply that figure by your electricity or gas unit rate to estimate the consumption cost.
Basic energy cost formula
- Measure usage
- Convert to kWh
- Multiply by your unit rate
Your actual energy bill may contain additional charges, so the result should be treated as an estimate rather than a supplier quote.
Appliance Electricity Cost Calculator
Want to know how much an appliance costs to run? The appliance section of the calculator lets you estimate running costs using appliance wattage, hours of use, quantity and your electricity unit rate. This can be used for household appliances as well as electrical equipment used in a business.
How do you calculate the electricity cost of an appliance?
Appliance running cost example
- Appliance
- 2,000W electric heater
- Running time
- 3 hours
- Electricity rate
- 26p per kWh
2kW × 3 hours = 6kWh
6 × £0.26 = £1.56
The estimated electricity consumption cost for those three hours. The actual amount can vary according to your tariff, appliance efficiency and how the equipment operates in practice.
Common examples you can calculate
MAKE THE NEXT MOVE
Want to see what your business could save?
Energy Solutions can review your usage, contract timing and
supplier options to help identify a more useful route to lower
energy costs. Start with a no-obligation conversation.
What Is a kWh?
A kilowatt-hour, or kWh, is the standard unit used to measure energy consumption. It is important not to confuse kW with kWh.
kW
Power. How much energy an appliance draws while it is running.
kWh
Energy used over time. This is what suppliers use when calculating your consumption charges.
For example, a 2kW heater running continuously for three hours would use:
2kW × 3 hours = 6kWh
Electricity Cost Calculator
You can also use the calculator as an electricity cost calculator to understand how changes in usage, appliance wattage or electricity prices affect what you pay.
Wattage
How much power the appliance requires.
Usage time
How long it operates.
Quantity
How many identical appliances or devices you use.
Electricity unit rate
The price you pay for each kWh.
For the most accurate estimate, use the electricity unit rate shown on your own bill rather than relying on an average.
Gas Cost Calculator
Gas consumption is also normally charged in kWh, although a gas meter may initially record the volume of gas used rather than displaying the final kWh figure billed by your supplier.
If you already know your gas consumption in kWh and your gas unit rate, the basic calculation is:
Worked example
A business used 1,000 kWh of gas during a period and paid 6p per kWh:
The estimated consumption charge would be £60 before any other applicable costs.
For domestic comparison only, Ofgem's average Direct Debit gas unit rate for 1 July to 30 September 2026 is 7.33p per kWh, with an average standing charge of 29.04p per day. These figures apply to domestic default tariffs rather than business energy contracts.
Business Energy Cost Calculator
For a business, even relatively small changes in energy consumption or unit rates can make a noticeable difference over a full contract year.
Our business energy cost calculator can help you estimate the cost associated with the energy your company uses and understand how usage affects overall expenditure.
How to Calculate Business Electricity Costs
If you know how much electricity your business uses, the basic calculation is straightforward:
Suppose a business uses:
- Annual consumption
- 30,000 kWh
- Contract unit rate
- 25p per kWh
Estimated consumption cost only. Final bills may include other charges.
How to Calculate Business Gas Costs
The same basic principle can be used for commercial gas:
For example:
- Annual consumption
- 50,000 kWh
- Contract unit rate
- 6p per kWh
Estimated consumption cost only, before applicable standing charges and other bill components.
Why Business Energy Costs Are Different
From Household Energy Costs
Business and household energy contracts should not be treated as the same thing. The Ofgem domestic energy price cap does not protect business energy contracts. Business prices depend on the supplier, contract structure and characteristics of the individual business supply.
Household energy
- Domestic tariff, typically a default or fixed household tariff
- Sits within the Ofgem price-cap environment
- Average rates published quarterly by Ofgem
Business energy
- Annual energy consumption
- Contract length and contract type
- Electricity or gas demand
- Meter and supply characteristics
- Wholesale market conditions
- Network costs and standing charges
- Taxes and levies
- When the contract is agreed
What Is a Standing Charge?
A standing charge is a fixed amount that may be charged for each day your energy supply remains connected, regardless of how much energy you use. This is separate from the amount you pay for each kWh of energy consumed.
Standing charges can therefore matter when comparing two tariffs, particularly for a site with relatively low consumption.
60p standing charge × 365 days = £219 per year
Do not judge an energy contract from the unit rate alone.
A lower unit rate paired with a much higher standing charge may not always produce the lowest total annual cost.
What Is the Climate Change Levy?
The Climate Change Levy (CCL) is an environmental tax that can apply to energy supplied to businesses and public-sector organisations.
CCL is therefore another reason why the final amount shown on a commercial energy bill can differ from a simple kWh × unit rate calculation.
Main Rates From 1 April 2026
Some businesses and supplies may qualify for exemptions or reduced rates. Check your own bill and contract documentation — this is general information, not tax advice.
Business tax information checked: August 2026. Source: HM Revenue & Customs.
Where Can I Find My Energy Unit Rate?
Your electricity or gas bill should normally show the unit rate you are paying. Look for a figure expressed as p/kWh or pence per kilowatt-hour.
Understanding these details can make it easier to review your existing contract and compare future options.
Energy Solutions' guide to understanding your energy bill explains the main information to look for when reviewing a business electricity or gas statement.
What to find on your bill
For business energy, check each of these before comparing options.
- Unit rate (p/kWh)
- Annual consumption
- Standing charge
- Contract end date
- Electricity MPAN, where relevant
- Gas MPRN, where relevant
- Current supplier
Why Calculate Your Energy Costs?
Calculating energy costs gives you a clearer view of where your money is going. For a household, this might help identify appliances that are expensive to operate. For a business, it can help you:
How Can a Business Reduce Its
Energy Costs?
There are two broad areas to consider.
Reduce how much energy you use
Look at where and when energy is being consumed. That could include reviewing:
- Lighting
- Heating
- Cooling
- Refrigeration
- Kitchen equipment
- Machinery
- Computers
- Equipment left running outside operating hours
Review what you pay for energy
Consumption is only one side of the equation. The other is the energy contract itself.
If your business is approaching the end of its current contract, reviewing available supplier options can help you understand whether the rates and terms currently available are suitable for your needs.
Calculated Your Business Energy Cost? Check Your Current Contract
Knowing what your business currently spends on energy is useful.
The next question is whether the contract behind that cost is still right for your business. Energy Solutions helps UK businesses compare commercial electricity and gas options and understand the rates, contract terms and costs involved before making a decision.
No pressure. Review your options and decide what works for your business. Send us your bill if you would prefer us to read the figures for you.
Frequently asked questions
Business Energy Calculator
Still unsure where to start?
Request a review and let the team identify the most relevant next step. There is no requirement to switch.
Is this calculator suitable for a business energy quote?
No. It is an estimate designed to help you understand the main cost drivers. A quote needs current contract terms, meter details, usage history and supplier pricing.
Should I enter the rate in pence or pounds?
Yes. Smart meters make the switch faster and more accurate. Most switches for smart-metered sites complete within 5 working days
What is a Letter of Authority (LOA)?
An LOA is simply a document giving us permission to negotiate with suppliers on your behalf. It is not a contract and does not tie you to a provider.
Does the business result include VAT and CCL?
VAT is included using the selected rate. CCL is included when the toggle is on, using the illustrative benchmark assumptions described above. Your business may qualify for different treatment.
Can I save or share my estimate?
Your inputs are saved locally in this browser for convenience. The Share button creates a link containing the current calculator settings where supported by your browser; it does not send data to a server.
Is the calculator suitable for all meter type
The energy calculator may not be suitable for all meter types, particularly Half-Hourly (HH) meters, as their consumption and billing structure can differ from standard meters.