What temperature should my home be in winter for health?

Above that floor, the comfortable range for the rooms you use most is 18 to 21 °C³. NHS advice adds a lower boundary for the most vulnerable: not below 16 °C for older people or those with impaired mobility⁴. This page sets out what each figure means, which rooms it applies to, and how bedrooms, empty rooms and time away from home change the answer.

18 °C: the floor for health

Eighteen degrees is the figure that recurs across official and independent guidance, and it is a health threshold rather than a comfort preference. The Met Office's winter advice is to heat your home to at least 18 °C, and it matters most for people with reduced mobility, those aged 65 or over, and anyone with a health condition such as heart or lung disease¹. The UK Health Security Agency advises maintaining at least 18 °C in the main living areas of the home to prevent poor health effects².

The same 18 °C figure appears in NHS advice relayed across independent guides: heat your home to at least 18 °C, and not below 16 °C for older people or those with impaired mobility⁴. Overnight, people who are 65 and over or who have pre-existing health conditions may find bedroom temperatures of at least 18 °C are needed¹.

For a household's energy independence, this floor is the number that sets the size of the heating task in winter. Every insulation upgrade, draught-proofing job or heating control improvement is, in effect, a way of holding 18 °C more cheaply and with less reliance on the boiler or the grid.

The comfortable range: 18 to 21 °C in the rooms you use

Above the floor, guidance converges on 18 to 21 °C for the rooms you spend most of your time in. The Centre for Sustainable Energy says those rooms should be between 18 and 21 °C to keep you warm and avoid damp building up³. Smart Energy GB relays the same range, noting the NHS advises keeping your home at least 18 °C during colder weather, especially if someone in the household is older or more vulnerable to the cold, and that most people find 18 °C to 21 °C comfortable in living spaces⁵.

The range is repeated across independent advice: the NHS recommends keeping your home at a minimum of 18 °C if you are over 65, not very mobile or have a health condition⁷, and Plymouth Energy Community echoes the Met Office line of heating to at least 18 °C⁸. For renters, the advice is not to go below 18 °C if there are health concerns, elderly people or small children in the house⁹.

Who needs the warmer end of the range

The 18 °C minimum is a floor, not a target, and some households are advised to sit at the top of the range. The Met Office singles out people with reduced mobility, those aged 65 or over, and people with heart or lung disease as the groups for whom the minimum matters most¹. Which relays NHS advice that anyone over 65, not very mobile or with a health condition should keep the home at a minimum of 18 °C⁷. Plymouth Energy Community adds that people with certain disabilities, children and the elderly fall into higher risk categories⁸.

Support exists to help these households hold that temperature. Scotland offers a range of payments to keep homes warm, from pension age winter heating to child and disability payments¹⁰. Under ECO Flex, households identified as low income and vulnerable, with an occupant whose health conditions may be impacted further by living in a cold home, can be referred through an NHS route¹¹. If holding 18 °C is difficult, the pages on cold homes and health and warm home prescription set out the help available.

Where the figures come from

The numbers on this page trace back to a small set of health bodies. The World Health Organisation's general advice is a home temperature of 18 to 21 °C¹², and the WHO and NHS together recommend keeping your home at 18 °C or warmer to protect your health¹³. The UK Health Security Agency's Cold Weather Plan for England sets the at-least-18 °C minimum for homes¹⁴. NHS guidance, as relayed by independent advisers, states your home should be at least 18 °C in rooms regularly used such as the bedroom or living room, especially if someone is older or more vulnerable⁵.

Around those health figures sits a body of independent consumer advice, from the Energy Saving Trust, the Centre for Sustainable Energy, Energy Systems Catapult and others, which translates the health minimum into thermostat settings and room-by-room practice. The health bodies set the floor; the consumer bodies explain how to reach it.

Why 21 °C is often the setpoint

Thermostats are usually set to between 18 °C and 21 °C¹⁵, and the Energy Saving Trust advises setting your thermostat to the lowest comfortable temperature, which for most people is between 18 °C and 21 °C¹⁶. British Gas Energy Trust puts it the same way: set your main room thermostat somewhere between 18 °C and 21 °C, a temperature comfortable for most people¹⁷.

The reason many homes settle at 21 °C rather than 18 °C is comfort. For healthy adults, a setting between 18 °C and 21 °C is often cited as the ideal comfort and efficiency zone², and the WHO figure allows reduction to as little as 18 °C for healthy adults¹⁸. Households with older or less mobile members usually need the top of the range. A programmable thermostat also lets you set a lower setback temperature, a minimum you do not want your home to drop below, for example not below 16 °C overnight or when you are out¹⁶.

Bedrooms at night: 16 to 18 °C

Bedrooms are the one place where guidance allows a lower temperature, because people sleep better slightly cooler. UK bedrooms are ideal at between 16 °C and 18 °C, possibly slightly higher for older adults⁵. The Centre for Sustainable Energy gives 18 °C as the recommended night-time bedroom temperature, though some people may be more comfortable in a slightly cooler room³.

The exception is vulnerability. NHS advice is not to go below 16 °C for older people or those with impaired mobility⁴, and the Met Office advises that people who are 65 and over or who have pre-existing health conditions may need bedroom temperatures of at least 18 °C overnight¹. For a baby's room, the guidance is covered separately on safe room temperature for a baby.

What to do when nobody is home

When the house is empty, the health minimum no longer applies, but another number takes over. If you are away for a period in freezing weather, leave the temperature set between 12 and 15 degrees to avoid the risk of burst pipes⁶.

For day-to-day absences, a setback temperature is the better tool: a minimum you do not want your home to drop below, such as not below 16 °C overnight or when you are out¹⁶. Home Energy Scotland also advises keeping your home heated to at least 15 °C during colder months to prevent condensation¹⁹.

Different rooms, different temperatures

The standard used in fuel poverty measurement gives a useful room-by-room picture: for households not needing an enhanced heating regime, the requisite temperature is 21 °C in the living room and 18 °C in other rooms²⁰. That matches the practical advice: heat the rooms you spend most time in to between 18 and 21 °C³, and do not go below 18 °C in a house with health concerns, elderly people or small children⁹.

This is where heating controls earn their keep. Thermostatic radiator valves and zoning let you hold 21 °C in the living room while bedrooms and spare rooms sit lower, which cuts the amount of heat, and money, needed to keep the household healthy. The dependence that remains is on the heating system and its fuel, whether that is gas, oil or electricity.

Why over-60s should not sit below 18 °C

For someone over 60 living alone, the threshold is firm. A substantial number of UK homes experience temperatures judged too low, below 18 °C, for the health of vulnerable people, including the over-60s and those in ill-health²¹. NHS advice is to keep the home at a minimum of 18 °C for anyone over 65, and not below 16 °C for older people or those with impaired mobility⁴.

Financial support recognises this group directly. The Pension Age Winter Heating Payment in Scotland is worth £203.40 per eligible household where the oldest person is under 80, and £305.10 for households containing a person aged 80 or over, for winter 2025/26²². A small number of people will need to apply²³. More on this group, including hypothermia risk, is on older people and home energy and hypothermia risk at home.

Health risk in a cold home, even when you feel fine

The health case for 18 °C does not depend on feeling cold. Cold homes can cause or worsen a range of serious health conditions including heart attacks, strokes, bronchitis and asthma²⁴. The same conditions are named again in fuel poverty sector guidance²⁵, and the Centre for Sustainable Energy adds that circulatory problems, diabetes, arthritis and mental health issues can be made worse by living in a cold home³.

The harm is cumulative and often invisible in the short term. A home that sits at 15 °C through winter may feel tolerable to a healthy adult, yet the health bodies' threshold exists because the evidence links sustained cold indoor temperatures to cardiovascular and respiratory harm. The wider context is on fuel poverty in UK households.

Reaching the temperature with less fuel

The cheapest degree is the one you do not have to generate. Holding the home at 15 °C or above in colder months helps prevent condensation¹⁹. Setting the thermostat to the lowest comfortable temperature, rather than a default, is the Energy Saving Trust's core advice¹⁶.

Good controls matter as much as the boiler: a main thermostat set between 18 °C and 21 °C¹⁷, radiator valves to warm only the rooms in use, and a setback temperature so the home never falls far enough for condensation to form on cold surfaces. Each of these reduces the heat, and therefore the fuel, needed to stay above the health floor.

Low all day or in bursts

On the question of steady low heat versus short bursts, the clearest guidance concerns damp. Having your heating on a constant low heat may be better for damp, and for your air temperature, than having it swing between hot and cold²⁶. The reason is physical: bursts of heat warm the air quickly but leave walls and window surfaces cold, so when the temperature drops again, moisture condenses on them.

A setback temperature is the practical middle path: the heating holds a floor such as 16 °C when the house is empty or overnight¹⁶, then recovers to the 18 to 21 °C comfort range when the rooms are in use. That keeps the fabric of the building warm enough to resist condensation without running at full temperature around the clock.