ONS data for 2023 showed around one in five deaths were preventable or treatable in England (21.6%) and Wales (22.7%), similarly to the previous year.
Northern regions in England had the highest rates of avoidable mortality with the lowest rates found in the south.
The avoidable mortality rate for the most deprived decile in England was 3.9 times higher than the least deprived for males and 3.5 times higher for females.
In Wales, the most deprived quintile's avoidable was 2.7 times higher than the least deprived quintile for both males and females.
There was a higher rate of avoidable mortality in the most deprived group compared with the least deprived group in all of the most prevalent causes of avoidable mortality in both England and Wales in 2023.
Mortality rates for males were higher than for females across all deprivation deciles in both countries.
Cancer remained the leading cause of mortality in England and Wales despite the declining rate followed by diseases of the circulatory system.
Avoidable mortality due to alcohol- and drug-related causes has increased since 2001 with the largest rises seen from 2019 onwards.
Anna Gazzillo, senior analytical manager at The Health Foundation, said: ‘Avoidable deaths are not just statistics; they are a stark reminder that too many lives are cut short unnecessarily. They reflect real failures in preventing illness and providing timely care. There is an urgent need for the Government to make good on its commitment to reduce unacceptable health inequalities and tackle the root causes of ill health. We need a comprehensive whole-Government approach and a renewed focus on prevention. And with the alarming rise in alcohol and drug-related deaths, local authorities need the security of multi-year funding and restoration of the public health grant.'
A Department for Health and Social Care spokesperson said: ‘Life chances and life expectancy should not be determined by where you live and we are lagging behind in many areas of public health. This Government inherited a broken NHS but through our Plan for Change, we will shift the focus of healthcare from sickness to prevention. We've already made a strong start by restricting junk food advertising on TV and online, and limiting school children's access to fast food, while the Tobacco and Vapes Bill will tackle our biggest killer and put us on track to a smoke-free UK.'