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COVID means UK migration data has fallen apart, just as the UK is introducing a new immigration system

05 Feb 2021

A collapse in UK migration data as a result of Covid-19 will leave migration policymakers effectively “flying blind” as the new post-Brexit immigration system comes into force, a new commentary from the Migration Observatory at the University of Oxford shows today.

The new analysis Where did all the migrants go? shows that following disruption to migration-related data collection, the UK does not currently have reliable data on:

  • How many immigrants arrived in the UK in 2020;
  • How many emigrants have left the UK in 2020;
  • How immigration and emigration are affecting the UK’s population;
  • How the characteristics of the migrant population have changed since 2019.

UK migration data has traditionally relied heavily on face-to-face surveys, such as the International Passenger Survey (IPS) – the key source of data for the UK’s immigration and emigration statistics since 1964. This has been suspended since March 2020. National Insurance Number (NINo) allocations to overseas nationals also usually provide data on foreign nationals entering the labour market, but these too have been disrupted due to Covid-19.

The other key survey – the Labour Force Survey (LFS) – provides data on the size and composition of the UK’s population, including migrants. However, an end to face-to-face interviews in this survey appears to have disproportionately reduced the number of migrants who participate. This has led to LFS data suggesting that the migrant population fell by nearly 900,000 in 2020, while an extra 1.25m UK-born people have ‘appeared’ in the figures despite there being no plausible demographic driver for an increase in the UK-born population.

The analysis shows that while there does appear to have been a decline in the UK’s migrant population in 2020, it is likely to be smaller than headline figures suggest. It finds that the strongest evidence of a decline in the migrant population is in London.

Madeleine Sumption, Director of the Migration Observatory at the University of Oxford said: “There is absolutely massive uncertainty about what is going on with migration at the moment, because all the data sources we normally use have been hugely disrupted. This has left us flying blind just as the UK is introducing a new immigration system, and will make it more difficult to understand the impacts of new policies.”

The Office for National Statistics is developing new data sources that should eventually help to address the dearth of data, and there will be a Census in March 2021 for England, Wales and Northern Ireland. As 2021 progresses, the Home Office will also start to produce data on the number of migrants using the new immigration system.

Sumption added: “Despite the uncertainty, it’s clear that Covid-19 has had an enormous impact on migration patterns. The big questions for 2021 will how long the disruption lasts and how broad its impacts are. How many people will want to use the new immigration system as Covid restrictions start to ease? Will people who have left the UK come back? Will the apparent shift away from London represent a ‘new normal’ or just a temporary phase?”

The report notes that any emigration that may have taken place as a result of the pandemic will not necessarily be permanent. Some migrants may have left the UK temporarily with the intention to come back after the pandemic—if their immigration status permits it.

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