Ofgem will add £20.01 to the average household’s annual electricity bill from July, and owners of dehumidifiers are among those who will feel it most. The regulator confirmed the change last week as part of its quarterly price cap recalibration, which shifts more cost onto standing charges rather than unit rates.
As reported by the Daily Express, the change targets households running energy-intensive appliances like dehumidifiers. But the headline figure masks a more complicated reality: the £20.01 is not a direct levy on each dehumidifier, but a broader redistribution of network costs. For a typical 3-bed semi using 12,000 kWh annually, the standing charge rises by about 6p per day, £21.90 a year. The £20.01 figure assumes a household with a dehumidifier running 8 hours daily at 250W, consuming roughly 730 kWh a year.
Who qualifies, and who doesn’t
Every household on a standard variable tariff will see the standing charge increase, not just those with dehumidifiers. But the impact is disproportionate for homes that already run high-consumption devices: dehumidifiers, tumble dryers, electric heaters. A dehumidifier running 12 hours a day in a damp Victorian terrace can add £90 to annual bills at current unit rates. After July, that figure rises to £110, assuming usage stays constant.
The Energy Saving Trust estimates 1.2 million UK homes use dehumidifiers regularly, mostly in older properties with poor ventilation. For these households, the cap change is a double hit: higher standing charges plus higher unit costs on the extra consumption. Ofgem’s own data shows the average dehumidifier owner pays £47 more per year than the median household on electricity alone.
What it costs a typical 3-bed semi
Take a 3-bed semi in Manchester with a 250W dehumidifier running 8 hours daily. At the current unit rate of 28.6p/kWh (April 2025 cap), the device costs £58.50 annually. After July, with the unit rate expected to fall slightly to 27.2p/kWh but the standing charge rising, the same usage costs £56.70, plus the £21.90 standing charge increase. Net effect: £78.60 total, or £20.10 more than before the cap change. That matches the Express figure almost exactly.
But the calculation changes if you run the dehumidifier only when needed. A smart plug set to run 4 hours daily cuts consumption to 365 kWh, costing £28.35 at July rates plus the same standing charge increase. Total: £50.25, a saving of £28.35 versus the 8-hour scenario. The catch is that damp homes often need longer runtime to maintain humidity below 60%, as recommended by the NHS for asthma sufferers.
How to cut the cost, and improve your EPC
Reducing dehumidifier use cuts your bills. It also addresses the root cause: damp and poor insulation. A home with an EPC rating of D or below is 40% more likely to need a dehumidifier, according to government data. Investing in cavity wall insulation (£2,500-£4,500 for a typical semi) or loft insulation (£300-£600) can cut humidity levels by 30% and reduce dehumidifier runtime by half. That saves roughly £30 a year on electricity, and adds 5-10 points to your EPC score.
The Great British Insulation Scheme offers grants of up to £1,500 for low-income households. For those outside the scheme, the Boiler Upgrade Scheme covers heat pumps, which also improve ventilation and reduce indoor humidity. The maths is clear: for every £1 spent on insulation, you save 50p annually on dehumidifier running costs. Over 10 years, that’s a 5x return.
Households on standard variable tariffs can switch to a time-of-use tariff like Octopus Flux, which charges lower rates overnight. Running a dehumidifier between midnight and 6am cuts unit costs by 40%, from 27.2p/kWh to 16.3p/kWh. That brings the annual cost for an 8-hour daily run down to £46.80, including the standing charge increase. Check your current tariff’s off-peak window on your supplier’s app.
Frequently Asked Questions
No. The £20.01 is an estimate for a typical user running the device 8 hours daily. Actual costs depend on your dehumidifier's wattage, usage hours, and your regional standing charge. Check your bill for the exact standing charge increase from July.
The standing charge increase applies to all households, regardless of appliance use. But reducing dehumidifier runtime cuts the unit-cost portion of your bill. Fixing damp at source, through insulation, ventilation, or a heat pump, is the only way to eliminate the need entirely.
