Calculating tumble dryer running cost

The formula is simple:

Cost per cycle = kWh used x unit rate (p/kWh) / 100

The two variables you need:

1. How many kWh your dryer uses per cycle. Check the product specification page or your model's energy label. If you cannot find it:

2. Your current unit rate. Check your electricity bill or your Octopus Agile app. For live Agile rates in your region, check AgileAlert now. The rate changes every 30 minutes on Agile.

A Tapo P110 smart plug (around £12) measures actual energy consumption per cycle for your specific machine. Running your dryer through it once gives you the precise kWh figure for your model rather than the industry average.

Condenser: cost per cycle at all tariff scenarios

A condenser tumble dryer using 2.5kWh per cycle costs:

The 95p peak Agile figure assumes the dryer runs entirely within a peak pricing half-hour. In practice, a 90-minute cycle spans multiple 30-minute slots. If those slots vary between 20p and 45p, the blended average cost per cycle is typically 55-75p during a peak evening. The 95p figure represents the worst-case scenario: running during the most expensive single window.

Heat pump: cost per cycle at all tariff scenarios

A heat pump tumble dryer using 1kWh per cycle costs:

At overnight Agile rates, each drying cycle costs 4p. That is less than the cost of boiling a kettle for a cup of tea.

Annual cost comparison

The table below shows annual running cost for both dryer types across all key tariff scenarios, at 250 cycles per year (the UK average of 4-5 loads per week).

Tariff Rate Condenser per cycle Condenser annual Heat pump per cycle Heat pump annual
Price cap 26.11p 65p £163 26p £65
Agile peak 38p 95p £237 38p £95
Economy 7 night 11p 28p £69 11p £28
Agile overnight 4p 10p £25 4p £10
Agile plunge 0p 0p £0 0p £0

The biggest single saving available to the average UK household is moving from peak pricing to overnight Agile timing on their existing condenser dryer: from £237 to £25, a saving of £212 per year. That is a weekend break. Four months of broadband. A new pair of shoes every other month.

Weekly and monthly cost reality check

Numbers become real when you break them into familiar units. Here is what 4 loads per week actually costs, month by month:

The difference between running at peak and running overnight: £13.60 per month. That is a meal out. Half a tank of petrol. A weekly shop's worth of difference over two months.

How to achieve overnight pricing: check AgileAlert each evening for your region's cheapest overnight window, then set the delay start on your dryer accordingly. It takes under two minutes. The monthly saving pays for that two minutes about 400 times over.

For a complete guide to setting delay start on your specific dryer brand, see the all-brands delay start guide.

What about part-loads and drying time?

The 2.5kWh figure is for a standard full cotton load. In practice:

The practical implication: batch laundry into full loads. A full load costs 10p overnight. Two half-loads cost approximately 14p overnight. Over a year of 4 loads per week, that 40% inefficiency from half-loading adds around £10 in unnecessary cost. Not enormous, but easily avoidable.

For the full picture of how timing decisions interact with usage frequency and dryer type, see the complete tumble dryer timing guide.

Frequently asked questions

Is a tumble dryer expensive to run?
It depends entirely on when you run it and what tariff you are on. A condenser dryer running at peak Agile prices (38p/kWh) costs £237 per year at average usage. The same dryer running overnight on Agile (4p/kWh) costs £25 per year. On a standard price cap tariff with no timing, it costs around £163 per year. The machine itself is not expensive to run. The habit of running it at the wrong time is.
Is it cheaper to use a tumble dryer or an airer?
An airer costs nothing to run. A tumble dryer at overnight Agile rates costs 10p per cycle. For households on Octopus Agile timing loads overnight, the financial difference is almost negligible. The real comparison involves time and convenience: an airer takes 4-24 hours depending on conditions; a dryer takes 60-90 minutes. For urgent or bulky items, the dryer's value is clear. For lightweight items with time to spare, the airer wins on cost. A detailed comparison is in the airer vs tumble dryer guide.
How do I reduce my tumble dryer running cost?
Three steps, in order of impact. First, shift to overnight Octopus Agile pricing (saves around £175/year on a condenser dryer). Second, run full loads rather than half-loads. Third, clean the lint filter before every cycle to maintain efficiency. If you also upgrade to a heat pump dryer, add another £98-142/year in savings depending on your tariff. The timing shift is always the biggest single lever.
How do I find my tumble dryer's actual kWh usage?
Check the energy label on the machine (required by law for all models sold in the EU and UK since 2021) or the product specification page on the retailer's website. The label shows kWh per cycle for a rated full cotton load. For real-world measurement, plug the dryer into a Tapo P110 or similar energy monitor smart plug. It displays exact kWh per cycle for your actual loads.