Understanding international migration in a rapidly changing world

Restrictions designed to halt the spread of COVID-19 have changed patterns of international travel dramatically. Jay Lindop explains how our migration statistics are changing to reflect this new context.

Before the arrival of the pandemic, long-term international migration to the UK had been following a broadly stable path since 2016. However, underlying this, clear differences have been emerging between EU and non-EU migration, as today’s release shows. In fact, non-EU migration had reached the highest level seen since we started collecting the information in 1975, driven by a rise in students from China and India.

Clearly the current restrictions have had a significant impact on travel – and therefore international migration to and from the UK. Using more up to date data from the Civil Aviation Authority, Department for Transport and Eurotunnel, we have also included some initial insights which show how international travel to and from the UK has decreased in recent months.

For instance, it shows that the volume of passengers moving between the UK and East Asia decreased significantly in February and March 2020, respectively, compared to the previous year. However, this is only a partial picture and represents all travel not just international migrants. Home Office has also published some information on recent passenger arrivals and will be publishing a fuller analysis of recent travel patterns next week.

It is important to note that these insights are not measures of international migration and should not be interpreted in this way. Rather, by exploring how recent international travel activity is likely to have changed, we’re able to provide an early picture of activity that supplements official statistics and may support policymakers and analysts in interpreting the current situation.

New data sources

This new evidence feeds into on-going work on the future of the ONS’s long-term international migration estimates.

Travel restrictions, enforced across the world, have affected travel to and from the UK since the turn of the year. They have also affected the ONS’ face-to-face survey operation, with the suspension of the International Passenger Survey (IPS) on 16 March 2020 and no current date for re-commencing.

While we have been able to include the IPS data in our latest migration estimates, and survey data will still be available for one more quarter, we are now planning to move away from the IPS and use administrative data to deliver new measures of migration from the end of 2020 onwards.

We have long acknowledged that the IPS, which underpins our existing international migration estimates, has been stretched beyond its original purpose and that we need to consider all available sources to fully understand international migration.

Now is the right time to focus our efforts on harnessing the power of administrative data for public good, building on the good progress already made through our population and migration transformation programme working alongside statisticians in other government departments.

Therefore, our August release will be the last set of quarterly migration statistics based on IPS data.

What will we use?

We know that there are challenges we need to overcome in order to deliver new measures of migration based on administrative data, including bringing in the further data we need to replace the IPS, understanding complex issues of interpretation and filling gaps in coverage.

As a result, our regular statistical reports will continue to be badged as Experimental Statistics throughout the transition, to support users in understanding the changes. As our transformation plans show, we will also highlight where we are unable to provide certain statistics or breakdowns of data whilst we build our new migration measures, alongside providing guidance on the quality and coverage to ensure the statistics can be interpreted appropriately.

We are also looking ahead to the implementation of the new immigration system in 2021 and working with Home Office and across the Government Statistical Service (GSS) to review how new administrative data could enhance our estimates of migration in future. This includes continuing our work with the Department for Work and Pensions to explore how their Registration and Population Interaction Database (RAPID) could be used for the purpose of measuring migration and population.

We will continue to keep users informed of our progress and welcome any feedback by emailing  pop.info@ons.gov.uk.

Jay Lindop is the Deputy Director of the Centre for International Migration