Last updated: April 2026
Learn how to read your gas and electricity bill, what each charge means, and how to spot errors or overcharging.
Every UK energy bill contains several key components: the standing charge (a daily fixed fee for being connected to the supply), the unit rate (the price per kWh of energy used), your total consumption in kWh, any government levies and VAT (charged at 5% on domestic energy), and your account balance showing any credit or debit. Understanding these components helps you compare tariffs accurately.
The standing charge is a daily fee you pay regardless of how much energy you use. It covers the cost of maintaining the gas and electricity network, your meter, and the supplier administrative costs. As of the April 2026 Ofgem price cap, standing charges are set at a maximum of around 61p/day for electricity and 32p/day for gas. Some tariffs offer zero standing charge options, but these typically have higher unit rates.
The unit rate is the price you pay for each kilowatt-hour (kWh) of energy consumed. Under the Ofgem price cap, the maximum unit rate is approximately 24.5p/kWh for electricity and 6.76p/kWh for gas (April 2026 rates). If you are on a fixed tariff, your unit rate may be different from the cap rate. Economy 7 customers have two rates: a cheaper night rate and a more expensive day rate.
If your supplier does not have a meter reading, they will estimate your usage based on historical data. Estimated bills can be significantly higher or lower than your actual usage. To avoid surprises, submit regular meter readings or get a smart meter installed. Smart meters send readings automatically, ensuring every bill is accurate.
Common bill errors include: incorrect meter readings (check the reading on your meter matches your bill), being charged the wrong tariff rate, being billed for estimated usage when you have submitted readings, and incorrect standing charge rates. If you find an error, contact your supplier with evidence. Under the back-billing rules, suppliers cannot charge you for energy used more than 12 months ago if the error was their fault.
High energy bills are usually caused by: increased unit rates (check if you are on the price cap or a higher tariff), higher usage during cold months, estimated billing that overestimates your consumption, or an inefficient boiler or poor insulation. Compare your kWh usage to the UK average (2,700 kWh electricity, 11,500 kWh gas per year) to see if your usage is typical.
A kilowatt-hour (kWh) is the standard unit for measuring energy consumption. One kWh is the amount of energy used by a 1,000-watt appliance running for one hour. For example, a 100W light bulb running for 10 hours uses 1 kWh. Your bill shows how many kWh you have consumed and the price per kWh.
Domestic energy is subject to VAT at a reduced rate of 5% in the UK, compared to the standard 20% rate for most goods and services. This reduced rate has been in place since 1994. The VAT is included in the unit rates and standing charges shown on your bill.
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Information sourced from Ofgem, Citizens Advice, and DESNZ. Last updated April 2026.
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