Cheapest Way to Dry Clothes Indoors UK

The Cheapest Method Depends on the Drying Job

Start with the whole load, not the hourly running cost.

A simple ranking such as heated airer first, dehumidifier second and tumble dryer last can be misleading. A device that draws little power each hour can still use more electricity overall if it has to run for much longer or repeat the job because the full washing-machine load does not fit.

Which? testing illustrates this capacity effect: heated airers can make sense for smaller loads, while larger loads that need multiple airer sessions can make a tumble dryer more competitive [S2]. The exact result depends on the appliances, load and programme you actually use.

For a useful comparison, calculate energy per completed load: appliance power in kilowatts multiplied by total runtime, including any repeated sessions. Then multiply the resulting kWh by your electricity unit rate.

Use Cost per Completed Load, Not Cost per Hour

The comparison unit should be the same finished job.

Cost per hour is useful for understanding an appliance, but it is a poor basis for declaring one drying method cheapest. If one appliance runs for two hours and another for eight, their hourly figures are not directly comparable.

For appliances with a rated wattage, a starting estimate is: watts ÷ 1,000 × total operating hours × electricity unit rate. If the method needs two sessions to handle one washing-machine load, include both sessions.

For a tumble dryer, a measured or manufacturer programme-energy figure can be more useful than multiplying its maximum rated input by cycle time, because power draw can change during the programme. Your own plug-in energy measurement, where appropriate and safe to use, gives the strongest household-specific comparison.

• Compare the same amount of laundry
• Include every session needed to finish that laundry
• Use your own electricity tariff
• Prefer measured energy where you have it
• Keep purchase price separate from running cost unless you are comparing total ownership cost

When an Unheated Airer Is the Cheapest Choice

It has no direct appliance electricity cost, provided slow drying works for your home.

An ordinary airer does not consume electricity, so it wins a narrow appliance-running-cost comparison. That does not mean every indoor environment can dry a load comfortably without additional moisture control.

Drying laundry releases moisture into the indoor air. If the room develops persistent high humidity or repeated condensation, deal with the moisture rather than treating free air drying as automatically consequence-free. Existing effective extraction or ventilation may be enough in some homes; other setups may benefit from a dehumidifier.

Do not add invented heating savings or assume an open window is free in winter. Heating, ventilation and weather interact, so those secondary effects need household-specific information rather than a universal pence-per-load estimate.

When a Heated Airer Can Be the Better Buy

It is most compelling when the load fits and one session completes the job.

Heated airers use relatively low electrical power compared with many high-heat drying appliances, but low wattage does not guarantee the lowest cost per completed load. Capacity and runtime matter just as much.

Which? reports that heated airers can save money for smaller loads, while the advantage can disappear for larger loads that require repeated uses [S2]. Treat published test figures as examples from tested products, not a universal tariff-independent price for your own airer.

A cover should not be assumed to cut the bill. Which? testing found that supplied covers or improvised coverings did not necessarily improve drying time and could trap humid air [S3]. Follow the appliance manufacturer's instructions rather than relying on a blanket cover claim.

When a Dehumidifier Changes the Decision

A dehumidifier is doing two jobs: supporting evaporation and removing water from the room air.

A dehumidifier can be useful with an airer because it removes moisture from the room as the laundry dries. This makes it different from a simple heat-only comparison: part of the electricity is buying humidity control as well as helping the drying setup.

Its cost still depends on electrical draw and runtime. Compressor cycling, room temperature, target humidity and the moisture load can all affect real consumption, so a static cost-per-session claim is weaker than using your own measured or labelled power data.

If your home already has a dehumidifier for condensation or damp-risk management, compare the incremental drying job carefully rather than assuming a second appliance must always be added.

When a Tumble Dryer Can Cost Less Than Expected

Large-load capacity and programme efficiency can outweigh a higher instantaneous power draw.

A tumble dryer should not automatically be placed last in a cheapest-to-most-expensive ranking. Which? testing found that for large loads, a heated airer needing multiple sessions can cost more overall than an efficient tumble-drying option [S2].

Dryer technology matters. Heat-pump, condenser and vented dryers should not be treated as one cost category, and individual models and programmes vary. Compare the energy required by the programme you use for the same load size.

If you already own the appliance, running cost per completed load is a useful decision metric. If you are deciding what to buy, separately consider purchase price, expected usage, capacity and lifespan rather than claiming that running-cost savings will repay a price difference within a fixed number of years.

A Practical Decision Order

Choose the lowest-cost setup that can finish the load while keeping indoor moisture under control.

First, decide whether an unheated airer can complete the load in acceptable conditions without repeated condensation. If yes, it has the lowest direct appliance energy cost.

If you need powered drying, enter your real load pattern into the laundry drying cost calculator. Compare total kWh for the complete job, including repeated heated-airer sessions, dehumidifier runtime or the tumble-dryer programme.

Then apply the moisture check. A cheap drying method that repeatedly leaves windows wet or pushes humidity up is not completing the household job well. Use the indoor-drying and humidity guides to decide whether extraction, ventilation or active dehumidification is appropriate.

• Small load and enough time: start with passive drying or compare one heated-airer session
• Large load: account for capacity and repeated sessions before declaring the heated airer cheapest
• Condensation-prone room: include moisture control in the decision
• Frequent large loads: compare the actual programme energy of your tumble dryer against the full alternative setup
• Any setup: improve the washing-machine spin where fabric care and machine settings allow, because less retained water means less drying work

Frequently asked questions

Bottom line

The useful answer is not a permanent ranking of appliances. Passive air drying has the lowest direct appliance energy cost, but once powered drying is needed the winner depends on load size, capacity, total runtime, repeated sessions and your tariff. Compare the same completed laundry job, then make sure the chosen setup also manages the moisture released indoors.