Skip to content

What do the 2014-based National Population Projections show?

This short story presents the main findings from the 2014-based national population projections. These replace the 2012-based projections we published in November 2013 and are based on the UK population at 30 June 2014. The national projections are produced by the Office for National Statistics on behalf of the National Statistician and the Registrars General of Scotland and Northern Ireland.

What are projections?

The projections are based on the most recently available mid-year population estimates and a set of underlying demographic assumptions regarding future fertility, mortality and migration. They are not forecasts and do not attempt to predict the impact that future government policies, changing economic circumstances or other factors might have on demographic behaviour, for example, government policies on immigration or student fees (however, the projections of people of pensionable age do take account of future changes in State Pension Age under existing legislation).

This story focuses on the first 25 years of the projections. A longer-term principal projection to mid-2114 is also available on the ONS website but this should be treated with caution in view of the increased uncertainty on demographic behaviour that far in the future.

What do these 2014-based population projections show?

The UK population is projected to increase by 4.4 million over the next decade, rising from 64.6 million in 2014 to 69.0 million at mid-2024. This increase, of 6.9% of the 2014 population, is equivalent to an average annual growth rate of 0.7% each year over the decade. Over the full 25 year period of the projection, the UK population is projected to increase to 74.3 million by mid-2039, with an annual average growth rate of 0.6%. It is projected that the population of the UK will reach 70 million by mid-2027.

Overall, this means that we are projecting that the population of the UK will increase by 9.7 million people (15%) over the next 25 years. Of the 9.7 million projected increase in the population over the full projection period to mid-2039, 4.7 million (49%) is due to projected natural change and 5.0 million (51%) is due to projected net migration.

How do natural change and net migration contribute over time?

Overall population growth is fastest in the first 5 years of the projection, with an increase in the population of 3.6%, equivalent to 2.3 million people by 2019. The slowest growth occurs in the 5 year period to 2039 (2034 to 2039) with only 2.2% growth, equivalent to around 1.6 million people. This occurs as the long-term assumptions for the projections are stable, but a short-term run-in or adjustment period, of 7 years for migration, is included to allow a gradual convergence to the long-term assumption as described in the migration assumptions paper. We assume constant levels of net migration in the long-term to avoid implying a level of accuracy that is not evidence-based. The effect for fertility assumptions is less pronounced, but the run in is longer, as described in the fertility assumptions paper.

Figure 1 shows the relative contribution of natural change and net migration over time to the growth of UK population. Natural change is the difference between births and deaths, and net migration is the difference between immigration and emigration. This figure shows that in the first 5 years of the projection, net migration plays the biggest role in population growth, but then for the following 10 years, natural change plays a greater role. This reverses again for the final 10 years of the projection period, where net migration becomes the stronger driver of population change again. The impact of net migration is fairly stable after the first 5 years (totally stable after 7 years as explained above), but natural change slowly declines over time, as more deaths occur, with fewer births taking place, as the rates align to the long-term assumptions.

Figure 1: Projected natural change versus net migration, UK, by 5 year period 2014 to 2039

Figure 1: Projected natural change versus net migration, UK, by 5 year period 2014 to 2039
Source: Office for National Statistics

Download chart

Past international migration has an indirect impact on the numbers of births and deaths – for example, women who were born overseas but who give birth after migrating to the UK will increase the numbers of UK births, while the numbers will be decreased by women born in the UK who migrate overseas before giving birth. Assumptions of future fertility and mortality are based on past trends of all residents irrespective of where they were born.

Because immigration is concentrated at young adult ages, the assumed level of future net migration has a more immediate effect on the projected number of women of childbearing age and hence the projected number of births, than on projected number of deaths. Of the 4.7 million natural increase projected between mid-2014 and mid-2039, only 3.1 million would occur if net migration were zero (at each and every age) throughout the projection period (Table 1). Thus about 68% of the projected increase in the population over the period mid-2014 to mid-2039 is either directly attributable to future migration (51%), or indirectly attributable to future migration through its effect on births and deaths (17%).

Table 1: Projected population growth by component, UK, mid-2014 to mid-2039

Total population increase between 2014 and 2039 9.69
Resulting from:
Assumed net migration 4.96
Natural change assuming zero net migration 3.06
Additional natural change from assumed level of net migration 1.67

Table source: Office for National Statistics

Download table

Care should be taken in interpreting these figures as "the indirect impact of migration". A fuller assessment of this would cover not only births to women who have migrated into the UK but also:

  • births to, and deaths of, people who had migrated to the UK before 2014

  • how to account for births to, and deaths of, UK-born people who had emigrated and subsequently returned to the UK

  • how to account for births to, and deaths of, UK-born people who had parents (or grandparents etc) who were themselves immigrants and the corresponding figures for foreign-born people descended from UK emigrants.

Why does this matter?

While the numbers can seem complex to interpret, important messages can be pulled out of the projections, to show how they will impact on everyday life and the requirements of future services.

Changing numbers of births and young people will change the requirements for midwives and schooling in the UK. In 2039, the number of UK births is projected to be about 6% higher than in 2014, at nearly 823,000 births. These babies and others born during the projection period will grow up needing schooling and childcare, and the population in need of primary school places (children aged 5 to 11) is projected to increase by 9.2% by 2039, and for secondary school aged children (children aged 12 to 16) this is projected to increase by 16.7% by the same year.

Over the same period, the number of people of working age is projected to rise by 11.4% from 40.0 million in mid-2014 to 44.6 million by mid-2039 (here we mean people aged between 16 and State Pension Age). This larger working population will have impacts on taxes collected by the government, as well as on the requirements for working age benefits.

Looking at the dependency ratio (which is the ratio of people of retirement age and over to working age people) we can see that the number of working age people available to support each retirement age person will change over time. In 2014 there were on average 310 people of retirement age for every 1,000 working age people, but by 2039 this is projected to increase to 370 people of retirement age for every 1,000 working age people. This has implications for the affordability of pensions as fewer workers are available to contribute to pay for state pensions via national insurance and taxes.

Aside from these obvious impacts there are more unpredictable ones. It is impossible to predict the exact impact of the population growth and change on housing or healthcare, but it is clear there will be an impact of an older and larger population on all aspects of life. Population projections are used in a wide range of planning purposes that impact on day-to-day life. Examples of the uses of the projections include:

  • the Office for Budget Responsibility use the projections as a main input to their long-term fiscal projections published in the fiscal sustainability report

  • the Department for Work and Pensions use the projections extensively to produce forecasts of expenditure for benefits and pensions and as a main input for analysis on policy areas such as extending working lives

  • the Department for Education use the projections as the basis for their projections of future school pupil numbers

  • the national population projections provide the base for other products such as subnational population projections and household projections, which are widely used for resource allocation and informing planning decisions by local authorities

Comparison with previous projections

This short story is part of the full release of the 2014 National Population Projections which includes detailed tables containing the projections for the UK and its constituent countries, as well as more detail on the assumptions made for the projections and how these assumptions were developed.

The population of the UK is projected to grow to 74.28 million in 2039. This is 420,000 higher than the 2012-based projection for 2039. This is partly attributable to the base 2014 population being 86,000 higher in the 2014-based projection than in the 2012 projections. The remainder of the difference reflects changes in the assumptions made in the 2014 projections and their impact as described in previous sections.

Table 2 shows a comparison of the average rate of growth over the next 25 years. It shows that the 2014-based projections predict a slightly faster rate of increase than the 2012-based projections did, equating to about an extra 14,000 people per year on average over the 25 years to 2039.

Table 2: Average growth rates for 2014-based projections compared with 2012-based projections

Projection Average growth per year % average growth per year
2012-based principal population projections 374,000 0.54%
2014-based principal population projections 388,000 0.56%

Download table

Where can I learn more about the population projections?

Separate releases for individual countries are also published by National Records for Scotland, the Northern Ireland Research and Statistics Agency, and Welsh Government statistics.

Information on how the projections are produced and the quality of the projections is provided in a Quality and Methodology Information (290.9 Kb Pdf) document.

An analysis of how close previous sets of projections have been to the subsequent population estimates is provided in the National Population Projections Accuracy Report (1.03 Mb Pdf) .

Information on previous sets of is available for 1954 to 2004 and for 2006 to 2012.

A high level description of the population-related statistics that we publish is available in the Overview of Population and Migration Statistics.

Categories: Population, Population Change, Population Projections, National Population Projections
Content from the Office for National Statistics.
© Crown Copyright applies unless otherwise stated.