Percentage of children in the overall population of the UK 1971-2023

The share of under 16s in the overall population of the United Kingdom was 18.3 percent in 2023, compared with 25.5 percent in 1971. Throughout this period, the share of under 16s in the overall UK population has declined significantly, with a brief uptick visible in the 1990s. 

Aging population in the UK

In 2001, the median age of the UK population was 37.9 years, with this increasing to 40.7 by 2022. Among UK regions, South West England had the highest median age in 2022, at 43.9 years, compared with just 35.9 years in London, the regions with the lowest median age. In the future, it is expected that the median age of the UK population will continue to increase. By 2050, it will reach 44.9 years, 48 by 2075, and by the end of the century the median age will reach 49.2 years. 

Challenges of an aging population

As the average age of the population gets older, the UK will face numerous challenges in adapting to this demographic change. With fewer people in the labor market, the government will raise less revenue, and struggle with increased expenditure on pensions. The UK is by no means alone in facing this challenge, with several countries, particular in Southern Europe and East Asia, facing similar demographic challenges. In 2050, for example, it is expected that 39.4 percent of the population of South Korea will be aged 65 or over.