The size of London’s population has changed dramatically over the past century; falling from a pre-Second World War high of 8.6 million people in 1939 to around 6.8 million in the 1980s. The fall was most pronounced in Inner London, which saw its population reduce by almost half over 50 years.
London’s population has been recovering since the early 1990s and hit a new high of 9 million in 2019. In a reversal of the mid-20th Century trend, both Inner and Outer London have been growing steadily, although Inner London is still a million people short of its population in 1931. By 2030, London’s population is expected to increase, but at a slower rate, with a total population of 9.4 million.
Data source: Mid-year population estimates (2020), Population of the UK by country of birth and nationality ONS (2020), via NOMIS. Ethnic group populations from Annual Population Survey ONS (2020), via London Datastore.
More than 9.0 million people live in London. Between 2010 and 2020, London’s population increased at a faster rate than the rest of England. Central London saw the biggest increase (14%), closely followed by East London with 13%. London’s overall growth of 10% is higher than the rest of England’s growth of 6%.
Central London has the highest level of population density with 12,475 people per km2, which is over twice the level of London overall. Still, London overall is 15 times more dense than the rest of England, with 5,727 and 369 people per km2 respectively.
40% of Londoners are Black and Minority Ethnic and 37% are not born in the UK. West London has the highest proportion (50%) of its population that are Black and Minority Ethnic and 40% who are not UK-born. These proportions are much higher in comparison to the population in the rest of England, where only 11% of the population are Black and Minority Ethnic and 11% are born outside of the UK.
Introduction
The 2020 mid-year estimate (MYE) is the current official estimate of the population for local authorities in England and Wales. The MYE contains estimates of both population and the components of population change (births, deaths and migration). The estimates are produced annually by the Office for National Statistics (ONS) and the 2020 MYE was published on 25 June 2021.
The 2020 MYE covers the period to the end of June 2020 and therefore includes the first three months of the coronavirus pandemic (April-June 2020). These estimates do not account for changes to the population which may have occurred since then.
Below is a summary of the 2020 MYE for London and London boroughs. In addition to the MYE data, a alternative population for 2020 based on recent trends in population change is provided for comparison. This GLA alternative estimate indicates what London's population may have been had recent trends continued without disruption into 2020.
Further information on population change in London since the start of the coronavirus pandemic is available in a GLA Demography report: //data.london.gov.uk/dataset/population-change-in-london-during-the-pandemic.
Key Points
- London's mid-2020 population was 9.002 million
- London grew by 40 thousand persons (0.45%) in the year to mid-2020
- There were 116 thousand births and 59 thousand deaths over the year resulting in a natural change of 57 thousand persons
- Net international migration for the period was an inflow of 85 thousand
- Net domestic migration was an outflow of 101 thousand
- Total net migration was therefore an outflow of 17 thousand
- The GLA estimates that had recent trends continued into 2020 without disruption London's population would have been 9.032 million, 29 thousand higher than the actual estimate
Population change
London's 2020 population was 9,002,488, a increase on 2019 of 40 thousand or 0.45%. This is the first time London's population has passed 9 million. National growth in England over the same period was 0.47%.
Age structure
International migration
Net international migration is the balance of people moving into London from overseas and those leaving London to non-UK destinations. London typically has a high international inflow and lower international outflow. This is partly because a significant number of the people that come to London as international migrants leave London for elsewhere in the UK making them domestic out migrants.
Average net international migration over the last decade (2010-2019) was 95 thousand persons per year. In 2020, net international migration was 85 thousand persons.
International in migration to London over the last decade averaged 197 thousand persons. As noted above, this is offset by both international out migration and domestic out migration. In 2020 there were 200 thousand international in-migrants to London.
Like international in migration, the level of international out migration fluctuates but remains within a relatively small range - over the last decade an average of 101 thousand people left London annually for locations outside the UK. In 2020 there were 116 thousand international out-migrants from London.
The difference between the GLA alternative 2020 estimate of international migration and the MYE is not significant. The GLA estimate has a lower international outflow and a higher international inflow than the ONS MYE, however the differences in the gross flows cancel each other and net international migration is similar in both estimates - they differ by just 18 thousand.
Domestic migration
Domestic migration is the movement of people within the UK. Net domestic migration shows the balance between those coming into London from elsewhere in the UK and those leaving London for somewhere else in the UK. As noted above, there is a strong relationship between international in migration and domestic out migration.
The axis on the chart is negative meaning that more people leave London than enter. In recent years the level of net domestic migration has been at very high levels. In 2020, 101 thousand more people left London than settled here.
The way that domestic flows are calculated was changed in 2017 to improve the quality of the data. However, as a result it is difficult to draw comparisons between the pre-2017 and post-2017 data. In 2020, 219 thousand people moved to the capital, a fall of 36 thousand on the 2019 flow.
Domestic outflows also decreased in 2020 compared to previous years. A total of 320 thousand people left London for another part of the UK in 2020, a fall of 29 thousand on the 2019 value.
Note that these data do not include moves between London Boroughs, only moves into and out of the capital.
London's population growth and structure are heavily influenced by domestic migration. Traditionally, young adults move to the capital in their 20s and early 30s for work and to take advantage of London's cultural offer. As the cohort ages they form partnerships and families and move out of London (along with many who initially came to the capital as international migrants) either to the commuter belt or further afield.
The impact of the pandemic on these established patterns of behaviour, and more broadly on the question of where people choose to live in the UK, has been an area of significant interest, debate and conjecture.
While the domestic gross flows of people in and out of London differed between the MYE and the GLA alternative 2020 estimate, the net flow was the same in both estimates (101 thousand).
Total migration
Total migration combines all four elements of migration - domestic in & out and international in & out - into one measure. Although London has large gross domestic and international flows the sum effect of these is not as significant as might be expected. The chart shows that total net migration is close to the zero line where all forms of migration cancel each other out. In 2020 the net balance of migration was an outflow of 17 thousand. This is very similar to the level seen in 2019.
Births
Births tend to be high in London and add significantly to the population. This is because the population of London, as an urban centre, is comparatively young and so the city has a high rate of family formation. That being said, births have been falling since they peaked in 2012. In 2020 there were 116 thousand births in London.
ONS have indicated that the estimate of births for mid-2020 is likely to be an undercount (of around 0.3%) due to delays in registrations. This implies London's births could be around 350 higher in reality than the figure given in the MYE.
Births is perhaps the component of change we would expect to be least affected in the initial stages of the pandemic. Full-term births occurring in the period April to June 2020 would have been conceived in August to October 2019, well before any cases of COVID-19 were reported. However, there may be some secondary impacts as disruption to patterns of migration may have changed where some births took place. The GLA estimates that had recent trends continued, there would have been 117 thousand births in London in 2020, one thousand more than the MYE total.
Deaths
The relatively young population structure of London means that the overall mortality rate is in the capital low. The number of deaths has remained relatively constant over the last decade (averaging 48 thousand per year). In 2020, there were 59 thousand London deaths. This significant increase is a result of the excess deaths from coronavirus.
London recorded 8,511 deaths from COVID-19 up to the end of June 2020. This is largely considered be an undercount of the actual total due to wrongly attributed deaths in the initial stages of the pandemic.
The number of excess deaths from coronavirus is not the same as the number of recorded deaths from COVID-19 - some of those who died from coronavirus would have died from other causes in the period to mid-2020 and these cases would not be considered excess deaths. Public Health England have attempted to calculate the number of excess deaths: for London they estimate an excess of 9,587 in the period from the start of the pandemic to the end of June 2020.
The GLA alternative estimate of deaths, based on recent trends in mortality rates, indicate that had those trends continued there would have been 49 thousand deaths in London in 2020. This implies excess deaths for the period of 10 thousand which is consistent with the PHE calculation.
Natural change
Natural change is the balance between births and deaths. In 2020 there were 57 thousand more births than deaths in London. This is lower than in previous years due to the excess of deaths in 2020.
The Impact of COVID-19
The impact of the coronavirus pandemic on London's population is difficult to disentangle from the published MYE data. One approach is to compare the MYE to a population calculated by applying recent trends in population change to the 2019 MYE. While the difference between these two populations is not solely the impact of COVID-19, this approach gives some indication of the extent to which the 2020 MYE varies from the recent series of estimates.
Table: London population and components of change, mid-2020
| Population | 9,002,500 | 9,031,500 | -29,000 |
| Births | 115,700 | 116,800 | -1,100 |
| Deaths | 58,800 | 49,100 | 9,700 |
| Natural Change | 56,900 | 67,700 | -10,800 |
| Domestic In | 218,900 | 239,800 | -20,900 |
| Domestic Out | 320,300 | 341,000 | -20,700 |
| Domestic Net | -101,400 | -101,200 | -200 |
| International In | 200,400 | 206,400 | -6,000 |
| International Out | 115,800 | 103,400 | 12,400 |
| International Net | 84,500 | 103,000 | -18,400 |
| Total Net | -16,800 | 1,800 | -18,600 |
The alternative population of London in the GLA estimate is 9.032 million, which is 29 thousand higher than the MYE value. Births in the mid-year estimate were slightly lower than projected while deaths were significantly higher. Net domestic migration was at the same level in both the alternative and actual estimates. International net migration was 18,400 lower in the MYE than the alternative value. Overall, the 2020 MYE is broadly consistent with recent estimates and the impact of the pandemic on London's population in the year to June 2020 appears limited.
Further information
The full ONS mid-year population estimates release and back series can be found on the ONS website: //www.ons.gov.uk/peoplepopulationandcommunity/populationandmigration/populationestimates.
For information relating to London's population see the demography pages of the London Datastore: //data.london.gov.uk/demography/ or email .
An in-depth review of the available evidence for population change in London since the start of the coronavirus pandemic has been produced by GLA Demography: //data.london.gov.uk/dataset/population-change-in-london-during-the-pandemic.
Issues with the 2020 mid-year estimates
Measuring population change during the pandemic has proved challenging. In some cases data collection processes have been disrupted (e.g. births registrations) while in other cases data collection has been stopped entirely (e.g. the international passenger survey). In other cases the accuracy of datasets may have been adversely affected by changes in behaviours not captured by standard processes (e.g. NHS GP register).
The last quarter of international migration data was modelled from Home Office data and then distributed sub-nationally based on past patterns because Migrant Worker Scan data was not available.
The ONS maintains that the 2020 MYE is an accurate estimate of the UK population and the output retains the Official Statistics designation. More information can be found on the ONS website: //www.ons.gov.uk/peoplepopulationandcommunity/populationandmigration/populationestimates/bulletins/annualmidyearpopulationestimates/mid2020#measuring-the-data
2021 Mid-Year Estimates
The 2021 MYE is scheduled for release in September 2022. This delay from the normal cycle of a June release is to enable ONS to incorporate early outputs from the 2021 census.
Note on the GLA Alternative 2020 population
The alternative mid-2020 population used for comparison in this report was produced using the GLA cohort component population model. This model operates at local authority district level and by single-year-of-age and sex.
The 2020 population was arrived at by calculating assumed levels of births, deaths and migration based on past observed rates to the 2019 MYE. The rates are all calculated by single-year-of-age and sex at local authority level:
- Fertility & Mortality - 2020 rates are calculated by trending forward with simple linear regression the observed fertility rates for the last 5 years.
- International out-migration - 2020 rates are calculated as the mean of the last 5 years of observed rates.
- International in-migration - 2020 levels are calculated as the mean of the last 5 years of observed inflows.
- Domestic migration - Migration between local authorities in England and Wales and cross-border flows between those authorities and Scotland and Northern Ireland are calculated as the mean of the last 3 years of migration rates.