Population size and structure

Southampton’s population size and structure

Understanding the size and structure of Southampton’s population and how it is changing is vital in estimating population need and for the planning and commissioning of services across the city. Data on Southampton’s population comes from a range of sources, using different methodologies for estimating the size and structure of the population and how this is projected to change in the future. These are summarised below, whilst links to the data and visualisation tools can be found in the resources section at the end of this page.

Residential population estimates

The Mid-year population estimates (MYE) are produced annually by the Office for National Statistics based on data from the latest Census, migration, births and deaths (known as natural change).

This estimate in known as the “usually resident population” and includes only people who have lived in the country for over 12 months. Visitors and short-term migrants are excluded. The MYE covers all of England,regions, local authorities and down to Lower Level Super Output Areas (LSOA), small areas covering between 1,000 and 3,000 people, there are 152 in Southampton.

A summary of the main points is provided below:

• In 2024, the resident population of Southampton was estimated to be 259,424, of which 128,859 (49.7%) are male and 130,565 (50.3%) are female
• Children between the ages 0 to 5 make up 6.3% (16,359) of the population, which is lower than the England average of 11.0%
• 17.4% (42,259) of Southampton’s resident population is aged between 16 and 24 years higher when compared to 10.8% in England. This is largely due to Southampton being a university city and home to approximately 37,800 students
• 13.7% (35,555) of the population are aged 65 and over which is lower than the England average of 18.6%

The main changes in Southampton wards are:

• Banister & Polygon has the largest ward population of 18,742 people or 7.2% of Southampton’s population
• The smallest ward, in population terms, is Harefield with a population of 13,585 people or 5.2% of Southampton’s population
• Swaythling (35.9%), Banister & Polygon (34.8%) and Bargate (29.3%) have the largest population aged 16 to 24 years reflecting the large student population in Southampton

More information on the ONS MYE can be found in the population estimate tool below and the resources section.

Small Area Population Forecast (SAPF)

Another way of looking at the resident population is using the Small Area Population Forecasts (SAPF) from Hampshire County Council, these estimates provide local estimates of the current and future resident population as they take account of natural change (births and deaths), internal and international migration and known and planned dwelling completions. The SAPF covers Hampshire, Portsmouth and Southampton. The estimates also include future dwellings supply based on residential planning applications.

The latest SAPF population projections run from 2024 to 2031 and suggest that the population of Southampton in 2026 is 257,976. The overall resident population is projected to increase by 4.6% (11,966 people) between 2026 and 2031. To 269,941 in 2031.

The number of dwellings is forecast to increase from 111,531 in 2026 to 117,306 in 2031; an increase of 5.2% (1,775 extra dwellings).

The largest growth in dwellings, in the same period, is predicted to be in Bargate (4,151 extra dwellings; 48.5%), followed by Bitterne Park (378 extra dwellings; 5.5%) and Banister & Polygon (299 extra dwellings; 5.5%). The smallest growth in dwellings is predicted to be in Coxford (5 extra dwellings 0.1%).

Detailed SAPF data including wards, neighbourhoods and by deprivation can be found in the population dashboard below or in the resources section the end of the page.

Subnational population projections (SNPP)

The SNPP from the Office for National Statistics take the mid-2022 population estimates, as their starting point and project the population to 2047. The projected local authority populations for each year are calculated by ageing on the population from the previous year, applying local fertility and mortality rates to calculate the number of projected births and deaths, and then adjusting for migration into and out of each local authority. The latest SNPP data runs from 2022 to 2047 and suggests that Southampton’s population by 2047 will be 281,498 and increase of 5.5% or 14,652 people between 2026 and 2047.

The SNPP are not forecasts. They do not consider possible future changes in international migration, or of population changes that could result from economic growth or housing policies. These factors are outside the scope of the projections.

The assumptions used for future fertility, mortality and migration are based on past trends. As a result, the projected figures are likely to differ from population estimates published in future years.

More details can be found in the population change section and in the dashboard below and resources section.

GP registered population

An alternative source of population data comes from GP practice registers; these provide the number of patients registered with a Southampton GP practice. The registered population differs from the resident population as a person can be registered with a Southampton GP practice but live outside the city, or may live in the city, but be registered with a GP practice outside of Southampton. For this reason, the registered population can be quite different to the resident populations. The GP registered population is particularly useful for the planning of public health services.

NHS Digital collates the registered population at GP surgery and Primary Care Network (PCN). The data is available by age and gender and is released monthly. In February 2026, there were 336,323 people registered at a Southampton GP, of which 162,303 (48.3%) were female and 174,020 (51.7%) were male.

More information on GP surgeries and PCN is available in the population dashboard in the resources section below.