Electricity vs Gas: Which Energy Bill Calculator To Use

UK households often notice that electricity bills are higher than gas bills — even when they use the same amount of energy. The reason is simple: electricity has a much higher unit rate than gas.

An energy bill calculator helps you compare electricity and gas costs side by side, showing how unit rates, standing charges, and energy usage affect your total bill. It uses actual Ofgem rates, regional data, and your own usage in kilowatt hours (kWh) to estimate realistic energy costs for your home. You can also use it to compare energy prices between suppliers and find the most cost-efficient tariff for your household.

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What’s the Difference Between Electricity and Gas Costs?

Both fuels are charged by the unit of energy (kWh) plus a daily standing charge that you pay even when you use no energy.

The price cap limits how much energy suppliers can charge per unit of gas or electricity on a standard variable tariff. But it doesn’t cap your total bill — the more energy you use, the higher your costs.

These averages come from Ofgem’s latest energy price cap data for a typical dual-fuel household using 2,700 kWh of electricity and 11,500 kWh of gas each year by direct debit.

How Are Energy Bills Calculated?

Your energy bill is based on both your usage and your tariff’s fixed charges:

Formula:
Total = (Unit Rate × Usage in kWh) + (Standing Charge × Days) + VAT (5%)

Example:
If you use 3,000 kWh of electricity and 12,000 kWh of gas per year, your total annual energy bill might look like this:

Your gas bill may show a higher total kWh, but the lower cost of gas per unit keeps it cheaper overall than electricity.

Why Does Electricity Cost More Than Gas?

The price of electricity in the UK is around four times higher per kWh than gas because of how it’s generated and taxed.

1. Gas Drives Electricity Prices

Even though renewable energy now supplies over 40% of UK power, much electricity still comes from natural gas plants. When the wholesale price of gas rises, the cost of electricity follows.

2. Carbon and Policy Costs

Electricity generation faces higher carbon taxes and green levies. Roughly 23% of the average electricity bill goes towards environmental and policy costs — compared to around 2% for gas.

3. Grid and Infrastructure Costs

Maintaining the National Grid and improving renewable integration adds to electricity’s standing charges, increasing your total bill.

4. Fossil Fuel Legacy

Older gas boilers and central heating systems remain cheaper to run because natural gas prices are still lower than electricity unit prices, even after recent energy price cap changes.

Your Next Bill Could Be Lower

Use our calculator to see what you’d save — takes under 6 minutes.

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Electricity Bill Calculator: How to Estimate Your Costs

An electricity bill calculator helps you understand how much you pay for lighting, heating, and household appliances.

It uses your electricity usage (in kWh of electricity), unit rate, and daily standing charge to estimate your monthly and annual electricity costs.

Example Calculation (Medium Household):

Electric heating, underfloor heating, or storage heaters will increase your electricity costs sharply. Households using heat pumps or electric vehicles (EVs) can enter higher electricity usage into the calculator to see realistic annual totals.

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Gas Bill Calculator: How to Estimate Your Gas Costs

A gas bill calculator works in the same way but uses lower unit rates and standing charges. Gas remains cheaper per kWh because it’s used mainly for heating and hot water, which require large amounts of energy.

Example Calculation (Medium Household):

Despite higher usage, gas bills are often smaller because gas costs less per kWh. However, if you use electric heating instead of gas central heating, your annual energy costs can easily double.

Estimate your gas bill with the calculator

Electricity vs Gas: Cost Comparison

Even before standing charges, electricity is about four times more expensive per kWh.

A smart meter helps track how much energy you use for each fuel in real time, giving you a better idea of your energy efficiency and total costs.

How Do Standing Charges Affect Gas and Electricity Bills?

Standing charges are fixed daily fees added to every bill, regardless of how much energy you use.

For low-usage homes or well-insulated flats, standing charges make up a large share of total costs. Even if you use no gas for heating during summer, you still pay these fixed charges to stay connected to the energy network.

What’s Better for Heating: Gas or Electricity?

Gas Heating (Central Heating & Boilers)

• Uses natural gas via a gas boiler to heat water for radiators and taps.
• Lower unit rate and upfront costs.
• Produces carbon emissions but remains cheaper than electric heating.
• Eligible for Boiler Upgrade Scheme if replacing older systems.

Electric Heating (Heat Pumps, Storage Heaters, Underfloor)

• Powered by electricity from the grid or renewable sources like solar panels.
• More efficient but has higher running costs due to expensive electricity prices.
• Reduces carbon footprint, especially if combined with renewable generation.

The efficiency of your heating system and your insulation level determine how much energy you actually need to maintain comfort at lower temperatures.

How Does Renewable Energy Change the Balance?

Using renewable energy sources like solar panels helps reduce energy costs over time. You can feed excess electricity back into the grid via SEG tariffs (Smart Export Guarantee).

If you generate your own power, your electricity bills drop significantly, although the upfront costs of installation can be high.

Households combining heat pumps with solar panels often achieve the lowest long-term heating costs and smallest carbon footprint.

Save More with Dual Fuel Energy Tariffs

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How to Compare Energy Prices and Choose the Right Tariff

The best way to manage rising energy prices is to use your calculator results to compare energy tariffs.

1. Check your energy usage in kWh.
2. Enter your unit rate and standing charge.
3. Compare fixed tariffs and variable tariffs to see which offers cheaper rates.
4. Look for renewable energy or green tariffs to cut emissions.
5. Pay by monthly direct debit for the lowest prices.

Compare energy prices to find the best tariff

FAQs About Electricity vs Gas Bill Calculators