There is no single running cost for an electric towel rail, because the answer depends on three things you can check yourself: the rail's power rating in watts, how many hours it is switched on, and the price per unit (kWh) on your own electricity tariff. Tariffs change, so this guide gives you the method rather than a number that will go out of date.
For the wider picture on electric heating, see our electric radiators and towel rails guide.
The calculation
- Find the wattage. It is on the product page or the rating label. If it is given in kW, multiply by 1,000 to get watts.
- Convert to kWh per hour. Divide watts by 1,000. A 100 W rail uses 0.1 kWh each hour it runs at full power.
- Multiply by hours on. Energy used (kWh) = watts ÷ 1,000 × hours.
- Multiply by your tariff. Look at your latest bill or supplier app for the unit rate in pence per kWh. Cost = kWh × unit rate.
Illustrative arithmetic only, not a product specification: a rail rated at 100 W running for 2 hours uses 0.2 kWh (100 ÷ 1,000 × 2). Multiply 0.2 by your own pence-per-kWh rate to get the cost. Replace the 100 W with the rating of the rail you are considering.
Why the real figure is often lower than the rating × hours
- Thermostats. If the rail or its controller has a thermostat, the element switches on and off to hold a temperature, so average power is lower than the rating whenever the rail has reached temperature.
- Timers. A programmer or built-in timer limits the hours it runs. Check each product page for what controls are included or supported.
- Room and towels. Insulation, ventilation and how many towels hang on the rail all affect how long it needs to run.
Ways to keep usage down
- Run it only when you need warm towels or a warmer bathroom, and use a timer if one is available.
- Choose an output that suits the job. A towel rail meant to dry towels does not have to heat a large room. Use our BTU calculator if you also want it to warm the space.
- Keep the bathroom ventilated and the rail clear so heat is not wasted.
Comparing models
Compare the wattage and the controls on each product page, then run the calculation above for each. Examples to browse include the Dante electric heated towel rail, the Vero electric heated towel rail and the Terma Alex One electric designer towel rail, or see all electric towel rails.
A note on safety and installation
Bathrooms are special locations for electrical installations. Fixed electrical connections must be carried out by a suitably qualified electrician to the current wiring regulations, so ask them to confirm a suitable position and connection.
Common mistakes
- Using an old or guessed tariff instead of the rate on your latest bill.
- Forgetting to convert watts to kilowatts.
- Assuming the rail draws its full rating for every hour it is switched on.
In short
Running cost = watts ÷ 1,000 × hours × your unit rate. Check the wattage on the product page, use your own tariff, and use timers and thermostats to keep hours down.