UK Population Statistics: Size, Growth and Projections

How big is the UK population?

The UK population was provisionally estimated at 69.9 million at mid-2025 by ONS. This is a provisional figure based on the confirmed mid-2024 estimate of 69.281 million plus provisional data on births, deaths and international migration in the year to June 2025. Full mid-2025 estimates with breakdowns by age, sex and local authority area are expected in summer 2026.

By country within the UK, England accounts for the vast majority of the population. At mid-2024, England had approximately 57.1 million people, Scotland 5.5 million, Wales 3.2 million, and Northern Ireland 1.9 million. England's population is growing faster than the other three nations.

Births, deaths and natural change

In the year to 30 June 2025, there were an estimated 653,000 births and 651,000 deaths in the UK. The difference -- called natural change -- was just 2,000 more births than deaths. This near-equality means that natural change is contributing almost nothing to population growth. ONS projects that deaths will exceed births every year from mid-2026 onwards. When that happens, the UK population can only grow through net migration.

The UK's Total Fertility Rate (TFR) -- the average number of children a woman is expected to have over her lifetime -- has been falling for years and stood at 1.44 in 2023, the lowest ever recorded and well below the 2.1 replacement rate. A TFR below 2.1 means that each generation is smaller than the one before it, putting long-term downward pressure on the birth rate even as women of childbearing age currently living in the UK are themselves products of higher-fertility years.

Net migration and population growth

Net migration -- the difference between people arriving in the UK for 12 months or more and people leaving -- was 204,000 in the year to June 2025. This is the main driver of UK population growth. Since 2020, almost all of the growth in the UK population has come from net migration rather than from births exceeding deaths. More than half (68%) of all UK population growth between 2005 and 2024 was attributable to net migration according to the Migration Observatory at Oxford.

Net migration peaked at 944,000 in the year to March 2023, driven by a surge in work visas (particularly health and social care), student visas, and humanitarian routes including the Ukraine and Hong Kong BNO schemes. Since then it has fallen sharply to 204,000 in year to June 2025, reflecting government immigration rule changes in 2024 and 2025 including restrictions on overseas students bringing family members and higher salary thresholds for Skilled Worker visas.

Population projections

ONS's 2024-based National Population Projections, published in April 2026, project that the UK population will grow from 69.281 million in mid-2024 to approximately 72.0 million by mid-2034. Over the 25 years to mid-2049, the population is projected to grow by 3.1 million to around 72.1 million. Net migration accounts for 180% of this projected growth -- the reason the percentage exceeds 100% is that without migration, the population would actually shrink because deaths are projected to outnumber births. The long-term net migration assumption used in the projections is 230,000 per year from mid-2027 onwards, which is the 10-year average of historical data. This assumption should not be read as a forecast -- it reflects a modelling convention, not a prediction.

The ageing population

The UK population is ageing. The median age was approximately 40.8 years in mid-2024, though this has decreased slightly from the mid-2021 Census figure, partly reflecting the composition of net migration (migrants tend to be younger than the existing population on average). Children under 16 are projected to fall from 18.2% of the population in mid-2024 to 15.5% in mid-2034. The working-age population will be supporting an increasingly large number of older people, with consequences for the NHS, social care, the pension system, and public finances.

People born overseas

Around 13.1 million people living in the UK were born overseas as of June 2024, equivalent to approximately 19% of the total population. This includes 3.9 million born in EU countries and 9.2 million born outside the EU. The Census 2021 recorded 10.7 million people born overseas (16% of the population at that time). The increase since then reflects continued high levels of immigration between 2021 and 2024.

What is the UK population in 2025?

The UK population was provisionally estimated at 69.9 million at mid-2025 by ONS. The confirmed mid-2024 figure was 69.281 million. Full mid-2025 estimates are expected in summer 2026.

Is the UK population growing or shrinking?

Growing, but almost entirely due to net migration. In the year to June 2025, births and deaths were nearly equal (653,000 births vs 651,000 deaths). From mid-2026, deaths are projected to exceed births, meaning net migration will be the only source of UK population growth.

What is the UK population projected to be in 2034?

ONS's 2024-based projections estimate the UK population will reach approximately 72.0 million by mid-2034 and around 72.1 million by mid-2049. Net migration is the only projected source of growth, as deaths are projected to exceed births from mid-2026.

How many people living in the UK were born overseas?

Around 13.1 million people (19% of the UK population) were born overseas as of June 2024, according to an ONS ad hoc estimate. This includes 3.9 million born in EU countries and 9.2 million born outside the EU.