Population change

Population change

Understanding how Southampton’s population will change in the future, and how this will affect demand for a range of services, is vital for service planning and commissioning. There are many uncertainties around current and future population numbers. The Small Area Population Forecasts (SAPF) produced by Hampshire County Council provides the best available estimate of how the resident population of the city will change over the short to medium term (currently up to 2031). In addition, long term population projections (currently up to 2047) are available from the Office for National Statistics.

Local population forecasts

The SAPF covers Hampshire and districts, Portsmouth and Southampton. These figures are based on natural change (births and deaths), internal and international migration and known and planned completions of residential dwellings.

The most recently published data is for the 2024 to 2031 period. The data for 2026 to 2031 forecasts that:

• Southampton’s total resident population is forecast to increase to 269,942 people by 2031, an increase of 4.6% (11,966 people)
• Within the city, the largest growth is predicted to be in Banister & Polygon an increase of 42.9% (7,509 people) between 2026 and 2031
• The ward with the lowest population change is Redbridge, with decrease -100 fewer people (-0.7%)

The change in dwellings, in the same period, are forecast to be:

• 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 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%) between 2026 and 2031

The proportion of the population of working age is steadily declining potentially impacting productivity and the skill pool of the resident workforce.

The older population is projected to grow proportionately more than any other group in Southampton in the next few years. The over 65 population is set to increase by 13.1%, or 4,940 people, between 2026 and 2031, with the over 75 population set to increase by 13.2%, or 2,394 people.

Combined with the decline locally and nationally in birth rates, there is an expected impact in the informal and community care available for the ageing population in the future. Further analysis into how a growing elderly population in the city may translate into demand for health and social care services has been undertaken locally.

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

Subnational population projections (SNPP)

These projections 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 and do not attempt to predict potential changes in international migration. There is uncertainty over future directions and levels of international migration. At the local level, population change is influenced by economic development and housing policies, factors that are not included in these projections.

Demographic assumptions for future fertility, mortality and migration are based on observed demographic trends. Resulting projections will differ to some extent from future releases of population estimates.

More information on the SNPP can be found in the population dashboard in the resources section.