---
title: "Does a dehumidifier lower your heating bills? | Home Comfort Lab"
description: "A drier home can be a little easier to heat, but a dehumidifier costs money to run. When it is worth running one and when it is not."
url: https://homecomfortlab.co.uk/heating/does-a-dehumidifier-lower-heating-bills/
---

# Does a dehumidifier lower your heating bills?

A drier home can be a little easier to heat, but a dehumidifier costs money to run. When it is worth running one and when it is not.

By [Pete Harvey](https://homecomfortlab.co.uk/about/), editor. Updated 14 October 2026.

![A living room with a person on the sofa, a warm radiator, a dehumidifier and a stack of coins on a side table.](https://homecomfortlab.co.uk/images/scenes/does-a-dehumidifier-lower-heating-bills.svg)

> **The short answer**
>
> Not by much, and often not at all. A drier home can be a little easier to heat, mostly because damp walls lose heat faster than dry ones. But the dehumidifier costs money to run, and in a home with gas heating that is likely to outweigh any saving. Run one to fix damp and condensation, and count any effect on your heating as a bonus.

## Why a damp home can cost more to heat

A damp home often feels colder than the thermostat says. Most of that comes from what the damp does to surfaces and fabrics, rather than from the moisture in the air itself.

- **Wet walls lose more heat.** Laboratory tests for the government's research into internal wall insulation found that wet bricks had higher heat loss than dry bricks. A wall kept damp by condensation lets more of your heating escape.
- **Damp fabrics feel cold.** Bedding, sofas and clothes that pick up moisture feel chilly and clammy against your skin, and it's tempting to turn the heating up to make up for it.
- **Moist air takes slightly more energy to warm.** Water vapour holds more heat than dry air does, but the amount is small next to the heat lost through walls, windows and draughts.

Only the first of these is likely to make a difference you would notice on a bill, and only if your walls are wet from condensation. If they are wet from rain getting in or from rising damp, a dehumidifier won't dry them for long. That needs a repair. See [the types of damp](https://homecomfortlab.co.uk/damp/condensation-vs-rising-damp-vs-penetrating-damp/).

## What the dehumidifier costs to run

Here is a worked example using a 12 litre compressor model (Pro Breeze OmniDry 12L), rated at 200W, running 6 hours a day:

| Period | Cost |
| --- | --- |
| Per hour | 5.3p |
| Per day (6 hours) | 32p |
| Per month | £9.60 |
| Over a 26-week winter | £57.48 |

A desiccant model costs more. The Meaco DD8L, at 650W, would cost £186.82 over the same winter. Both figures assume the machine works flat out for every one of those hours. With the humidistat set to 50 to 60%, it cuts back once the room is dry, so the real cost is often lower.

Costs use **26.32p per kWh**, the [Ofgem price cap, Direct Debit average for England, Scotland and Wales](https://ofgem.gov.uk/news/changes-energy-price-cap-between-1-october-and-31-december-2026) for 1 October to 31 December 2026. Your own tariff may differ. [How we calculate](https://homecomfortlab.co.uk/how-we-calculate/).

[Running cost calculator](https://homecomfortlab.co.uk/tools/running-cost-calculator/): Put in your own dehumidifier's wattage and hours to see what it costs you.

## Where the electricity goes

Almost all the electricity a dehumidifier uses ends up as heat in the room. It also releases the heat that went into turning the water into vapour, as the water turns back into liquid. That heat came out of your room when the water evaporated, so it is a refund rather than a gift, but it does mean a dehumidifier gives off a little more heat than the electricity it uses. In winter, that warmth isn't wasted.

The catch is the price. At the current cap, a kWh of electricity costs about 3.3 times as much as a kWh of gas. A boiler loses some heat up the flue, so the real gap is a little smaller, but heat from a dehumidifier still costs more than heat from gas central heating. If you heat with plain electric heaters, it is a different story: the dehumidifier's warmth costs no more than theirs, and you get the drying as well.

> **About percentage savings**
>
> You may see claims that a dehumidifier cuts heating bills by a set percentage. We haven't found independent research that supports a figure like that for UK homes, so we don't give one.

## When it's worth running one

- You have condensation, a musty smell or mould. Fixing that is the main reason to own one.
- You dry washing indoors. A dehumidifier stops that water ending up on your walls, and usually costs less than a tumble dryer. See [drying clothes indoors without damp](https://homecomfortlab.co.uk/damp/dry-clothes-indoors-without-damp/).
- You heat with electric heaters, so the dehumidifier's warmth costs about the same as theirs.
- A cold room needs drying. A desiccant model's heat is useful there.

## When it isn't

- Your home already sits between 40 and 60% humidity with no condensation. Running one then mostly costs money. A cheap hygrometer will tell you; see [ideal indoor humidity](https://homecomfortlab.co.uk/damp/ideal-indoor-humidity/).
- You're running it only in the hope of a lower gas bill.
- The damp is from a leak, rain getting in or rising damp. That needs fixing at the source.

## Cheaper ways to cut damp and heating costs together

- Open trickle vents and use extractor fans when cooking and showering, so moisture leaves before it settles.
- Keep a low, steady background heat in cold rooms rather than heating them hard now and then. Warmer walls collect less condensation.
- Draught-proof doors and letterboxes, and use film on single glazing. See [draught excluders and window film](https://homecomfortlab.co.uk/heating/draught-excluders-and-window-film/).
- Dry washing in one closed room, not across the house.

## Sources

- [BEIS Research Paper 2021/016: Thin Internal Wall Insulation, Annex D, Moisture risks of TIWI: laboratory investigations](https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/975990/tiwi-annex-d.pdf)

Checked 14 October 2026.

## Read next

- [Dehumidifier running costs: popular models compared](https://homecomfortlab.co.uk/damp/dehumidifier-running-costs/) (Running costs)
  What each popular dehumidifier costs per hour and per month at the current price cap, from its rated power.
- [Appliance running cost calculator](https://homecomfortlab.co.uk/tools/running-cost-calculator/) (Calculator)
  Find out what any electric appliance costs per hour, day, month and winter at the current UK price cap.
- [Heated airer running costs](https://homecomfortlab.co.uk/heating/heated-airer-running-costs/) (Running costs)
  What heated clothes airers cost per hour and per load at the current price cap, and how that compares with a tumble dryer.
- [Electric blanket and heated throw running costs](https://homecomfortlab.co.uk/heating/electric-blanket-running-costs/) (Running costs)
  What electric blankets and heated throws cost per hour, per month and per winter at the current price cap.

---

As an Amazon Associate I earn from qualifying purchases. Links to shops are marked, and earning from them never decides what we recommend. [How this site is paid for](https://homecomfortlab.co.uk/affiliate-disclosure/).

Running costs use 26.32p per kWh for electricity and 7.97p per kWh for gas, the [Ofgem price cap, Direct Debit average for England, Scotland and Wales](https://ofgem.gov.uk/news/changes-energy-price-cap-between-1-october-and-31-december-2026) for 1 October to 31 December 2026.