New Office for National Statistics analysis covering 1988 to 2025 estimates that cold days have killed far more people than hot ones across England and Wales — but the gap is narrowing as temperatures rise.
Nearly 200,000 deaths in England were associated with the coldest days between 1988 and 2022, compared with just over 51,000 linked to the hottest days, according to ONS data. The figures show that cold has historically been the dominant temperature-related killer — but the proportion of deaths tied to the hottest days has increased and the balance between the two is shifting.
For the South East region, which includes Kent, the ONS estimated 3,800 cold-related deaths and 1,900 heat-related deaths in the five-year period 2018 to 2022 alone — equivalent to 8 deaths per 100,000 population for cold and 4 per 100,000 for heat. Kent residents are directly captured in those regional figures.
The ONS analysis covers all-cause mortality, using relative risk models that compare death rates on the hottest and coldest days against an “optimal” temperature. Hottest and coldest days are defined using regional temperature distributions — typically the 97.5th and 2.5th percentiles of the regional temperature distribution. The models find that mortality risk in England rises at temperatures above roughly 22°C, with London recording the highest heat-related relative risk: at temperatures above 29°C, mortality risk was around three times that seen at optimal temperatures.
Older adults face a sharper rise. For people aged 65 and over, analysis linked to ONS methodology points to at least a 50 per cent increased mortality risk at temperatures above about 24°C, compared with optimal temperatures. Cold risk rises steeply too — the models estimate a mean relative risk increase of around 1.06 per degree drop below the cold threshold.
Kent’s population skews older than the national average, which matters here. Kent County Council, Medway Council, and the NHS Kent and Medway Integrated Care Board hold responsibility for local implementation of national heat-health and cold-weather plans.
The ONS notes that data for temperatures below roughly −6°C and above 30°C is limited, so estimates at those extremes are treated with caution. National figures for the extended 1988–2025 period — reported in national media as around 40,063 heat-related deaths and 138,944 cold-related deaths in England — have not yet been cross-checked against the primary ONS tables and should be treated as unverified.
Key information
- Heat-health alerts and cold-weather warnings are issued nationally by the UK Health Security Agency — check UKHSA guidance during extreme weather episodes
- Kent County Council and Medway Council can direct residents to local support schemes covering fuel poverty, home insulation, and emergency cold-weather assistance
- NHS Kent and Medway ICB provides health advice for vulnerable residents, including older people and those with cardiovascular or respiratory conditions, during temperature extremes
- Checking on neighbours aged 65 and over or those in poor-quality housing is recommended by public health guidance during both heatwaves and cold snaps
Source: @ONS