United Kingdom · 7 tools

Energy & Bills calculators

Rebuild a household bill from usage, unit rate and standing charge, then test a cap or solar scenario.

Most used

Start here, then explore the groups below.

Electricity CostCalculate your electricity costs per day, month and year based on your usage and unit rate.Energy & Bills Gas BillCalculate your monthly and annual gas bill from your daily usage, unit rate and standing charge.Energy & Bills Solar Panel SavingsCalculate solar panel savings, payback period and 10-year return based on your system size and energy prices.Energy & Bills Energy BillCalculate your total annual energy bill combining gas and electricity usage, unit rates and standing charges.Energy & Bills

Rebuild the bill from unit rate, standing charge and use

Household energy tools are useful when you can see whether the unit rate, the standing charge or the kWh is driving the total. Compare a current bill with a cap or solar scenario on the same usage, not on a headline unit price alone.

Enter usage from a recent bill (kWh or cubic metres) rather than a round guess.
Keep standing charges in the same units as the calculator (often pence per day).
Test a second usage level if the household pattern is about to change.

Usage, unit rate, standing charge

Energy calculators translate the messy reality of UK utility bills — unit rates, standing charges, regional variation, dual-fuel discounts — into numbers you can actually budget with. With the Ofgem price cap refreshing every quarter, it pays to rerun these tools when your tariff changes.

Most households pay for energy in two layers: a fixed daily standing charge regardless of usage, plus a per-kWh unit rate. Your total bill is the sum of those across your consumption. These tools apply the current regional rates to whatever usage figures you plug in, so you can see what a behavioural change (thermostat setting, EV charging pattern, induction hob vs gas) actually costs over a year.

Solar is increasingly worthwhile in the UK — not because of dramatic sunshine, but because the numbers work even at modest generation once you factor in rising unit rates, SEG export payments, and battery storage. The Solar Panel Savings calculator runs realistic UK scenarios (north/south facing, shading, export tariff) to give you a pre-quote sanity check.

Start with the combined Energy Bill calculator for a whole-household view, then drill down with Electricity or Gas separately if only one is changing. The Water Bill calculator uses Water UK’s 2026/27 company averages for England and Wales. The Solar calculator is a useful pre-read before inviting an installer to quote — if the maths looks thin, you know what questions to ask.