Boiler Running Cost Calculator UK
Instantly compare gas, oil or electric boiler running costs per hour. Enter your boiler’s output, efficiency and fuel price to see which fuel saves you money.
How It Works
Running cost per hour = Output (kW) ÷ (Efficiency / 100) × Fuel price (£/kWh). A more efficient boiler uses less fuel for the same output, lowering your cost.
For tips on improving efficiency, see our Boiler Efficiency & Maintenance Guide.
Fuel Price Comparison
Gas prices fluctuate less than oil; electric rates vary by tariff. Check current UK rates on the BEIS statistics.
Improving Boiler Efficiency
Regular servicing and powerflushing can restore efficiency. Learn more in our Boiler Maintenance Tips.
Upgrading Your System
Modern condensing boilers achieve >90% efficiency. Compare models in our Best Boilers 2025 review.
Project Values
| Entity | Attribute | Value |
|---|---|---|
| Boiler Run | Fuel type | Gas, Oil, Electric |
| Boiler Run | Output | kW |
| Boiler Run | Efficiency | % |
| Boiler Run | Fuel price | £/kWh |
Frequently Asked Questions
Which fuel is cheapest?
Generally gas runs cheapest, oil mid-range, and electric most costly per kWh.
How does efficiency affect cost?
Higher efficiency means less fuel input for the same heat output, lowering hourly cost.
What output should I enter?
Use your boiler’s rated output in kW (e.g., 24 kW for a typical home system).
Can I use this for a whole heating system?
Yes—enter combined heat output and overall efficiency for your complete system.
