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.
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.
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.