How to Read a UK Energy Bill Before You Switch

Find the tariff name and dates

Start with the tariff name, billing period and whether the bill is based on actual or estimated meter readings. These details tell you what period the costs relate to and whether the consumption figure is reliable enough for comparison.

Find the unit rates

Look for the electricity and gas prices in pence per kWh. If you have Economy 7 or another multi-rate tariff, you may see separate day and night rates. Note them exactly and check whether VAT is already included in the displayed figure.

Find the standing charges

Bills normally show a daily standing charge for each fuel. Multiply the daily amount by 365 if you want a quick annualised figure. This helps prevent a low unit rate from looking better than it really is when the standing charge is high.

Find annual consumption

Many suppliers show estimated annual consumption or a rolling annual kWh figure. This is extremely useful when comparing quotes because the same consumption number can be entered into different supplier calculators. If the bill only shows one month, look for an annual statement or sum a longer period.

Check meter readings and balance

Before switching, submit accurate readings where possible and understand whether your account is in credit or debit. A switch does not erase an existing balance with your old supplier. Keep copies of final readings and closing statements.

Check bill periods and estimated reads

A bill based on estimated meter readings can make short-term consumption look unusual. Where possible use a twelve-month kWh figure and confirm recent meter readings, especially if you have moved, installed an EV charger, changed heating or had a long period away from home.

Numbers worth writing down

Before comparing, note your tariff name, electricity and gas annual consumption in kWh, current unit rates, daily standing charges, payment method and any exit fees. If your bill only shows consumption for a shorter period, look for the supplier’s annual estimate or total the available statements carefully.