1.3 How many international migrants are moving to each local authority?
The three charts in this section explore some of the ONS Local Area Migration Indicators Suite (LAMIS) and the Scottish Local Area Migration statistics. These datasets contain several different kinds of information that can be used to understand migration into and out of local authorities each year:
Long-term international migration (LTIM) includes people of any citizenship (UK or non-UK) moving to the UK for at least a year.
Short-term international migration (STIM) includes non-UK citizens moving to the UK for 3-12 months for the purpose of employment or study.
Internal migration includes people of any citizenship already resident in the UK moving between local authorities. Note that the majority of these people are expected to be UK citizens.
National Insurance Number (NINo) registrations include non-UK nationals newly registering for a NINo who recently entered the UK or have lived in the UK for some time without a NINo. These data include information on local authorities in Northern Ireland.
GP registrations cover people of any citizenship who register with a GP for the first time and report that their previous address was abroad.
Births to Non-UK Born Mothers provide estimates on new births to mothers who were born outside the UK.
The International Passenger Survey (IPS) measures migration flows to and from the UK and form the basis of immigration, emigration and net migration estimates in the ONS Migration Statistics Quarterly Report. Separate estimates are produced for long- term (12+ months) and short-term (up to 12 months) migration. To produce estimates at the local authority level the ONS uses the published estimates of long-term immigration totals and then uses administrative data to distribute the total across local authorities. Similarly, for short-term immigration estimates, the ONS uses published short-term immigration totals derived from the IPS data for non-British workers and students staying for 3 to 12 months (UN definition). The worker and student totals are then distributed by mapping the IPS definitions as closely as possible to the relevant data within the administrative sources provided by other government departments. In both cases, the national-level IPS estimates come with margins of error, and the local- level numbers are also estimates rather than precise figures.
IPS estimates are not sufficient to measure migration to Northern Ireland, because it does not account for movements across the Irish border. The Northern Ireland Statistics Agency (NISRA) supplements ONS quarterly migration figures with GP registrations data. One result of this is that short-term migration estimates are not available for Northern Ireland. Supplementary analysis of the data for Northern Ireland, which is available through the ONS, is also available from NISRA.
Margins of error in survey data
Caution must be used when examining estimates of small groups because of margins of error. Estimates represent what is considered to be the most likely figure, but the true number could be higher or lower. APS and IPS data are reported with 95% confidence intervals which indicate the margins of error. For example, the estimated non-UK born population residing in the UK in 2018 was 9,342,000, with a confidence interval of +/- 146,000. One effect of this is that it may not be sensible to make too much of the difference between two estimates – small differences may result from statistical noise rather than real changes in the population. Users should look at the trend over several years as in some cases the apparent year on year change may be misleading.
In some local areas, confidence intervals are quite wide relative to estimates of the population of interest. For example, the estimated non-EU born population living in Sunderland was 8,000 in 2017 and 2018, with a confidence interval of +/-4,000. The corresponding estimate for the year 2016 was 6,000. In other words, the data do not show with certainty that the non-EU born population of Sunderland changed between 2016 and 2018.
What are the best data sources to understand arrivals of people from outside of the UK to different local authorities?
ONS estimates of long-term and short-term immigration inflows should be the first port of call for users interested in the overall picture of new arrivals to an area.
Figure 6 shows long-term inflows to local authorities across the UK.
Figure 7 shows short-term inflows to local authorities in England and Wales; short-term inflows are unavailable at the local level in Scotland and Northern Ireland.
Note that while ONS provides estimates to the nearest individual (eg, 3,401 people), in order to facilitate further calculations based on the data, these are only estimates based on a survey that has confidence intervals and should not be considered to be as exact as the figures imply.
The International Passenger Survey (IPS) measures migration flows to and from the UK and form the basis of immigration, emigration and net migration estimates in the ONS Migration Statistics Quarterly Report. Separate estimates are produced for long- term (12+ months) and short-term (up to 12 months) migration. To produce estimates at the local authority level the ONS uses the published estimates of long-term immigration totals and then uses administrative data to distribute the total across local authorities. Similarly, for short-term immigration estimates, the ONS uses published short-term immigration totals derived from the IPS data for non-British workers and students staying for 3 to 12 months (UN definition). The worker and student totals are then distributed by mapping the IPS definitions as closely as possible to the relevant data within the administrative sources provided by other government departments. In both cases, the national-level IPS estimates come with margins of error, and the local- level numbers are also estimates rather than precise figures.
IPS estimates are not sufficient to measure migration to Northern Ireland, because it does not account for movements across the Irish border. The Northern Ireland Statistics Agency (NISRA) supplements ONS quarterly migration figures with GP registrations data. One result of this is that short-term migration estimates are not available for Northern Ireland. Supplementary analysis of the data for Northern Ireland, which is available through the ONS, is also available from NISRA.
Margins of error in survey data
Caution must be used when examining estimates of small groups because of margins of error. Estimates represent what is considered to be the most likely figure, but the true number could be higher or lower. APS and IPS data are reported with 95% confidence intervals which indicate the margins of error. For example, the estimated non-UK born population residing in the UK in 2018 was 9,342,000, with a confidence interval of +/- 146,000. One effect of this is that it may not be sensible to make too much of the difference between two estimates – small differences may result from statistical noise rather than real changes in the population. Users should look at the trend over several years as in some cases the apparent year on year change may be misleading.
In some local areas, confidence intervals are quite wide relative to estimates of the population of interest. For example, the estimated non-EU born population living in Sunderland was 8,000 in 2017 and 2018, with a confidence interval of +/-4,000. The corresponding estimate for the year 2016 was 6,000. In other words, the data do not show with certainty that the non-EU born population of Sunderland changed between 2016 and 2018.
In addition to the long-term and short-term immigration inflow data, other sources of data can provide insights into migration at the local level. Although NINo registration data only cover people entering the formal labour market for the first time, they can be broken down by nationality at the time of registration, at the local authority level. This is not possible with the other frequently updated sources.
To understand more about the limitations of using NINo registration data for understanding migration, click here.
Figure 8 shows NINo registrations by non-UK nationals in 2018 for EU vs. non-EU citizens. The Department of Work and Pensions (DWP) provides further breakdowns for 14 different world regions. Its online system, Stat-Xplore, allows users to examine the data by age, gender and nationality at the local authority level from within their internet browser.
ONS local indicators also include data on the number of GP registrations by people moving to the UK from abroad. These data may be useful alongside the other data sources to provide insight into service planning, particularly in health care, but they do not provide substantial additional information beyond the short-term and long-term migration figures discussed earlier. Indeed, GP registrations are one of the data sources used to calculate the ONS short-term and long-term immigration estimates.
Figure 9 describes how these different datasets capture different types of migration.
Figure 8: NINo registrations by nationality and UK local authority (year ending June 2019)
National Insurance Number (NINo) data provide information on non-UK national at the point they first register for a national insurance number, with data provided by local authority (the place of residence rather than the place of work). A NINo is generally required for anyone who wants to work or claim benefits, but will exclude many people who are neither working nor claiming benefits, including children. It is therefore not a measure of international migration inflows, because applicants may have come to the UK months or even years before registering and because some migrants will not have NINos. A person can only register once for a NINo, so if they leave the UK for several years this will not be recorded and if they return they will not be included in the new registrations data the second time.
Country groupings do not include the UK and, unless otherwise specified, are as follows:
EU-14: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Italy, Luxembourg, Netherlands, Portugal, Republic of Ireland, Spain and Sweden.
