Migration Statistics Quarterly Report: February 2020

Other international migration outputs released today (27 February 2020) can be found on the following pages:

• Home Office, Immigration Statistics, year ending December 2019
• Department for Work and Pensions, National Insurance number allocations to adult overseas nationals: January 2002 to December 2019

Also released today (27 February 2020) is an update of the progress with the preliminary adjustments for long-term international migration statistics so far, which includes a summary of our main areas for further research and development and a request for feedback.

As part of our transformation journey we are making use of all available data sources to provide a richer and deeper understanding of migration. We published our first set of preliminary adjustments in the August 2019 Migration Statistics Quarterly Report (MSQR) to produce our best possible assessment of migration trends.

In this release we have made small refinements to the preliminary adjustment methods. These refinements have had minimal impact on the estimates. The methods applied in the current preliminary adjustments are described in Long-term International Migration (LTIM) estimates methodology.

While we go through this transformation journey, the MSQR has been reclassified as Experimental Statistics to support this period of development and innovation to meet the public good.

To align Short-Term International Migration (STIM) estimates with the transformation programme, we have reviewed what we are due to publish in May 2020. For more information please see the Transformation overview update.

To fully understand long-term international migration trends, we need to consider all available data sources. Throughout this report, we provide our best assessment of migration trends given data availability.

In the year ending September 2019, long-term international migration continued to add to the UK population, as an estimated 240,000 more people moved to the UK with an intention to stay for 12 months or more than left the UK (net migration). Over the year, 642,000 people moved to the UK (immigration) and 402,000 people left the UK (emigration).

Long-term net migration, immigration and emigration have remained broadly stable since the end of 2016. However, there are different patterns for EU and non-EU migration – both overall and by main reason for migration.

Since 2016, there has been a decrease in immigration for work, but recently levels have remained broadly stable. Over the same period, immigration for study has been gradually increasing.

EU migration

From March 2016, no preliminary adjustments were applied to EU migration estimates and as such, we have made our best assessment based on all the available evidence.

• EU net migration has fallen since 2016, although more EU citizens still arrive long-term than leave.
• This is mostly driven by a decrease in those coming to the UK, alongside a gradual increase in the number of EU citizens leaving the UK over the same time period.
• The number of EU citizens coming to the UK for work-related reasons has decreased to the lowest level since 2004, driving the overall fall in immigration for work since 2016.
• The decrease was initially a result of fewer EU citizens coming to the UK looking for work; however, since 2018, the number of people arriving with a definite job has also fallen.

Non-EU migration

• Non-EU net migration has gradually increased since 2013 and is now at the highest level since 2004.
• This is because of an increase in those coming to the UK, now at the highest level on record, with the number of non-EU citizens leaving the UK over the same time period remaining broadly stable.
• The increase since 2016 is mainly because of a gradual rise in the number of non-EU citizens coming to the UK for formal study; this is a trend reflected in all available data sources, with sponsored study visa applications for universities at the highest level on record.
• Since 2013 all available data sources have shown gradual increases in the number of non-EU citizens coming to the UK for work-related reasons.

Asylum, humanitarian protection, alternative forms of leave and resettlement

In the year ending December 2019, the latest available Home Office statistics also published today show that the UK offered protection in the form of grants of asylum, humanitarian protection, alternative forms of leave and resettlement to 20,703 people, up 30% compared with the previous year to levels last seen in 2003.

Statistician’s comment

“While long-term net migration, immigration and emigration have remained broadly stable since the end of 2016, different trends have emerged. EU net migration has fallen, while non-EU net migration has gradually increased since 2013 and is now at the highest level since 2004.”

“Since 2016, immigration for work has decreased because of fewer EU citizens arriving for a job. Meanwhile, immigration for study has gone up and is now the main reason for migration. This is driven by more non-EU students arriving, specifically Chinese and Indian.”

Jay Lindop, Director of the Centre for International Migration, Office for National Statistics.

Follow ONS Director of the Centre for International Migration @JayLindop_ONS

In the year ending September 2019, long-term international migration continued to add to the UK population as an estimated 240,000 more people came to the UK with an intention to stay 12 months or more than left the UK (net migration). Over the last year, 642,000 people moved to the UK (immigration) and 402,000 people left the UK (emigration).

Since the end of 2016, long-term net migration, immigration and emigration have remained broadly stable (Figure 1). Some variations in these trends have occurred over this time period, however we recommend users look at the broader evidence and longer time series, which allow a better assessment of trends.

Figure 1: Long-term immigration, emigration and net migration have remained broadly stable since the end of 2016

Long-term international migration, UK, year ending December 2009 to year ending September 2019

Source: Office for National Statistics – Long-Term International Migration (LTIM), LTIM with preliminary adjustments based on Department for Work and Pensions and Home Office data

Notes:

1. The data in the charts represent our best available estimates. Different types of lines have been used to represent where adjustments have and have not been applied. Solid lines indicate adjustments have been applied (see note 2). Dashed lines indicate no adjustment has been made yet due to data availability.
2. Preliminary adjusted immigration and net migration estimates for EU8 citizens have been produced for the year ending December 2009 to the year ending March 2016, and preliminary adjusted emigration and net migration estimates for non-EU students have been produced for the year ending December 2012 to the year ending September 2019.
3. Confidence intervals for the unadjusted estimates are not shown in the chart but are available in the accompanying dataset.
4. Confidence intervals for the preliminary adjusted estimates are not yet available. This does not mean that the estimates are more certain. As we refine our methods, we will develop our approach for displaying uncertainty around estimates based on multiple data sources.
5. YE equals year ending.

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While overall migration levels have remained broadly stable since the end of 2016, patterns for EU and non-EU citizens have followed different trends. This in part reflects the different trends in immigration for employment and study, with EU migrants predominantly arriving for work-related reasons (see Section 8) and non-EU migrants arriving for study (see Section 9).

EU net migration has fallen following peak levels in 2015 and 2016, while non-EU net migration has gradually increased since 2013 and, as at the year ending September 2019, is the highest level since 2004 (Figure 2). For both EU and non-EU citizens, more people come to the UK than leave the UK and they therefore continue to add to the UK population.

Figure 2: Non-EU net migration has increased since 2013, while EU net migration has decreased since 2016

Net migration by citizenship, UK, year ending December 2009 to year ending September 2019

Source: Office for National Statistics – Long-Term International Migration (LTIM), LTIM with preliminary adjustments based on Department for Work and Pensions and Home Office data

Notes:

1. The data in the charts represent our best available estimates. Different types of lines have been used to represent where adjustments have and have not been applied. Solid lines indicate adjustments have been applied (see note 2). Dashed lines indicate no adjustment has been made yet due to data availability. In addition no adjustment has been applied to the data for British Citizens.
2. Preliminary adjusted net migration estimates for EU8 citizens have been produced for the year ending December 2009 to the year ending March 2016 and preliminary adjusted net migration estimates for non-EU students have been produced for the year ending December 2012 to the year ending September 2019.
3. Confidence intervals for the unadjusted estimates are not shown in the chart but are available in the accompanying dataset.
4. Confidence intervals for the preliminary adjusted estimates are not yet available. This does not mean that the estimates are more certain. As we refine our methods, we will develop our approach for displaying uncertainty around estimates based on multiple data sources.
5. YE equals year ending.

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While the international migration of EU and non-EU citizens continues to add to the UK population, the long-term trend for British citizens is that more leave the UK than return to the UK (Figure 2).

Since the year ending September 2018, there has been a decrease in net migration of British citizens to levels last seen in 2012. In the year ending September 2019, 73,000 more people left the UK for 12 months or more than arrived over the same time period. This recent decrease is driven by a rise in the number of British citizens leaving the UK for 12 months or more alongside a slight fall in those returning to the UK.

Decisions to migrate are complex, and a person’s decision to move to or from the UK will always be influenced by a range of social and economic factors.

EU net migration has fallen since 2016

Following peak levels of over 200,000 in 2015 and early 2016, EU net migration has declined and stands at 64,000 in the year ending September 2019. This is largely because of a fall in EU immigration (Figure 3). This is reflected by a decrease in the number of EU migrants arriving in the UK with the intention of staying for 12 months or more for work-related reasons (see Section 8).

Since 2015, EU emigration has increased, but has remained broadly stable in the last two years. Despite these trends, there were still more EU citizens moving to the UK to stay for 12 months or more than were leaving the UK.

Figure 3: EU net migration has fallen since 2016, but more EU citizens move to the UK than leave the UK

EU long-term international migration, UK, year ending December 2009 to year ending September 2019

Source: Office for National Statistics – Long-Term International Migration (LTIM), LTIM with preliminary adjustments based on Department for Work and Pensions and Home Office data

Notes:

1. The data in the charts represent our best available estimates. Different types of lines have been used to represent where adjustments have and have not been applied. Solid lines indicate adjustments have been applied (see note 2). Dashed lines indicate no adjustment has been made yet due to data availability.
2. Preliminary adjusted immigration and net migration estimates for EU8 citizens have been produced for the year ending December 2009 to the year ending March 2016.
3. Confidence intervals for the unadjusted estimates are not shown in the chart but are available in the accompanying dataset.
4. Confidence intervals for the preliminary adjusted estimates are not yet available. This does not mean that the estimates are more certain. As we refine our methods, we will develop our approach for displaying uncertainty around estimates based on multiple data sources.
5. YE equals year ending.

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The decline in EU net migration since 2016 was a trend seen for all EU groups. The largest decrease has been seen in EU8¹ citizens (Figure 4). In the last year, net migration for EU2¹ citizens has more than halved, driven by an increase in those leaving the UK. While net migration for EU15¹ citizens has fallen since 2016 it has remained broadly stable in the last two years. For both the EU2 and EU15 (and EU nationals as a whole) there are still more people arriving to stay for more than 12 months than leaving.

As noted, preliminary adjustments have only been applied to the EU8 group for the year ending December 2009 to the year ending March 2016. It is possible that once an adjustment is applied, net migration among this group could change.

Figure 4: The fall in EU net migration since 2016 was a trend seen among all EU groups

Net migration by EU group, UK, year ending December 2009 to year ending September 2019

Source: Office for National Statistics – Long-Term International Migration (LTIM), LTIM with preliminary adjustments based on Department for Work and Pensions and Home Office data

Notes:

1. The data in the charts represent our best available estimates. Different types of lines have been used to represent where adjustments have and have not been applied. Solid lines indicate adjustments have been applied (see note 2). Dashed lines indicate no adjustment has been made yet due to data availability.
2. Preliminary adjusted immigration and net migration estimates for EU8 citizens have been produced for the year ending December 2009 to the year ending March 2016.
3. Confidence intervals for the unadjusted estimates are not shown in the chart but are available in the accompanying dataset.
4. Confidence intervals for the preliminary adjusted estimates are not yet available. This does not mean that the estimates are more certain. As we refine our methods, we will develop our approach for displaying uncertainty around estimates based on multiple data sources.
5. YE equals year ending.

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Non-EU net migration has gradually increased since 2013

An estimated 250,000 more non-EU citizens moved to the UK than left in the year ending September 2019. This net estimate has gradually increased since 2013 and, as at the year ending September 2019, is at the highest level since 2004. This is largely because of a rise in non-EU immigration, now at the highest level on record, while emigration has remained broadly stable (Figure 5).

Looking at all available data sources, the rise in non-EU immigration since 2016 is mainly driven by more migrants arriving for formal study. Since 2013 there has been a gradual increase in the number of non-EU citizens coming to the UK for work-related reasons (see Section 8).

Figure 5: Non-EU net migration has gradually increased since 2013, to the highest level since 2004, mainly driven by a rise in those coming to the UK

Non-EU long-term international migration, UK, year ending December 2009 to year ending September 2019

Source: Office for National Statistics – Long-Term International Migration (LTIM), LTIM with preliminary adjustments based on Department for Work and Pensions and Home Office data

Notes:

1. The data in the charts represent our best available estimates. Different types of lines have been used to represent where adjustments have and have not been applied. Solid lines indicate adjustments have been applied (see note 2). Dashed lines indicate no adjustment has been made due to data availability.
2. Preliminary adjusted emigration and net migration estimates for non-EU students have been produced for the year ending December 2012 to the year ending September 2019.
3. Confidence intervals for the unadjusted estimates are not shown in the chart but are available in the accompanying dataset.
4. Confidence intervals for the preliminary adjusted estimates are not yet available. This does not mean that the estimates are more certain. As we refine our methods, we will develop our approach for displaying uncertainty around estimates based on multiple data sources.
5. YE equals year ending.

The increases in non-EU immigration since 2013 have mainly been driven by a rise in the number of Asian citizens – particularly South Asian and East Asian citizens coming to the UK, now at 265,000 in the year ending September 2019, a trend reflected in all available data sources.

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Notes for: EU and non-EU migration over time

1. See the Glossary for further information on EU groupings.

While remaining the two most common reasons to move to the UK, there have been different patterns in the estimates for work and study. From the year ending March 2019, study has overtaken work as the most common reason to move to the UK, for the first time since the year ending September 2012 (Figure 6).

The decrease in work-related immigration since 2016 is mainly driven by fewer EU migrants arriving in the UK with the intention of staying for 12 months or more for work-related reasons (see Section 8). Over the same time period there has been a slight increase in the number of non-EU migrants arriving to work (see Section 9).

The Office for National Statistics (ONS) produces estimates of the labour market activity of the resident population in the UK by nationality and country of birth.

For the period October to December 2019, the latest estimates from the Labour Force Survey (LFS) show that there were an estimated 2.31 million EU nationals working in the UK, and an estimated 1.34 million non-EU nationals working in the UK.

Looking over the longer time series, since 2009 the number of EU nationals working in the UK has generally increased but has been broadly flat since the latter half of 2016. The number of non-EU nationals working in the UK remained broadly stable up until early 2019 but has increased slightly since.

Immigration for work-related reasons has fallen since the year ending June 2016 and can largely be accounted for by a decrease in EU citizens moving to the UK for work. Following a peak of 190,000 in the year ending June 2016, the number of EU citizens arriving for work has fallen to 79,000, the lowest level since 2004. This fall in work-related immigration was seen among all EU groups (EU15, EU8 and EU2).

Initially this decrease was driven by those moving to the UK looking for work, followed by a decrease in EU citizens moving to the UK with a definite job.

This pattern was different across the EU groups. For EU15 and EU2 groups the decrease in immigration for work-related reasons was driven by both those looking for work and with a definite job. However, for EU8 citizens this was driven more by a decrease in those looking for work (Figure 7).

Figure 7: Immigration to the UK for those coming with a definite job and looking for work shows different patterns across the EU groups.

EU15, EU8 and EU2 work-related long-term immigration trends by those arriving with a definite job and looking for work, UK, year ending December 2009 to year ending September 2019

Source: Office for National Statistics – International Passenger Survey

Notes:

1. Confidence intervals for the IPS-based estimates are not shown in the chart, but they are available in the accompanying dataset.
2. See the glossary for further information on EU groupings.
3. YE equals year ending.
4. Estimates for 2019 are provisional.

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Foreign citizens require a National Insurance number (NINo) to work in the UK, and NINo registration data can provide another view of work-related immigration. Following a recent peak in 2015, the total number of EU NINo registrations has been falling, in line with the fall seen in the International Passenger Survey (IPS) data (Figure 8).

For EU citizens, the latest available data show that there were 456,000 NINo registrations in the year ending December 2019. The recent increases in registrations should be seen in context with increased operational capacity and the processing of outstanding applications. It is important to remember that NINo registrations data are for all NINo registrations regardless of length of stay or date of arrival. Previous research on NINo interactions data concluded that NINo registrations will include short-term migrants and people who may have been in the country for a while before registering.

Immigration for study is the most common reason for non-EU citizens moving to the UK and has gradually increased since 2016

As has been the long-term trend, formal study remains the most common reason for non-EU citizens coming to the UK, at 165,000 in the year ending September 2019.

All available data sources have shown an increase in the number of non-EU students arriving in the UK (Figure 9). Following a gradual increase since 2016, the overall number of people estimated to arrive in the UK intending to stay for 12 months or more for formal study is 228,000 in the year ending September 2019, the highest level since 2011. Latest available Home Office visa data in the year ending December 2019 show that the number of Tier 4 (sponsored study) visas granted was 285,508, its highest level since the year ending June 2011.

This increase in immigration has largely been driven by a rise in Asian citizens coming to the UK for formal study, at 139,000 in the year ending September 2019. Home Office visa data show that Chinese nationals accounted for 42% of the 285,508 sponsored study visas granted in the year ending December 2019 and has more than doubled since 2012. Indian nationals accounted for a further 13%, almost doubling in the latest year (now at 37,540 grants) and continuing to increase since 2016.

The majority (86%) of sponsored study visa applications in the year ending September 2019 (latest available data) were to study at higher education (university) institutions, and the number of non-European Economic Area (EEA) nationals arriving at universities was the highest level on record.

All available data sources show an increase in non-EU citizens coming to the UK for work since 2013

Following an increase between 2013 and 2017, non-EU immigration for work has remained broadly stable over the last two years.

All available data sources have shown increases in the number of non-EU citizens coming to the UK for work since 2013 (Figure 10).

In the International Passenger Survey (IPS), the number of non-EU citizens arriving with a definite job has increased since 2013, now at 78,000 in the year ending September 2019. However, following a peak of 24,000 in the year ending June 2016, the number of non-EU citizens coming to the UK looking for work has fallen to 9,000 in the year ending September 2019.

Latest available Home Office data shows that the number of work-related visas (including short-term or temporary work) granted in the year ending December 2019 was 193,517, its highest level since 2007. In the year ending December 2019 (latest data available), there were 308,000 NINo registrations from non-EU nationals, an increase of 45% on the previous year. The noticeable increase in NINo registrations to non-EU nationals since September 2018 is mostly because of registration for a NINo of adult dependents as part of certain visa approvals.

Home Office visa data and NINo registrations are consistent with trends in the IPS showing an increase in Asian citizens arriving in the UK for work. In the year ending December 2019, the number of work visas granted to Asian nationals was 116,308, the highest level since the year ending March 2007, before the “points based system” was introduced. Of these, 68% (79,176) were for Skilled (Tier 2) work, the highest level on record. Indian nationals accounted for half of the skilled work visas granted in the year ending December 2019, although there have also been increases in Nigerian and Philippine nationals in the latest year. Over the same time period, there was an increase of 90% in NINo registrations for Asian nationals, to 176,000 in the year ending December 2019.

Home Office data also show that 59% of non-EU work migrants come to the UK for skilled work (Tier 2 visas) which has increased by 11% to 113,958 (including short-term or temporary work) in the year ending December 2019, the highest level on record. The number of Tier 2 visas has been rising steadily since July 2018, when doctors and nurses were removed from the Tier 2 cap.

Notes for: Non-EU immigration to the UK

1. Home Office entry clearance work visas issued for 12 months of more for main applicants only.

Home Office statistics show that in the year ending December 2019 the total number of people granted protection increased to 20,703. This was up 30% on the previous year to levels last seen in 2003 and consisted of:

• 12,565 grants of asylum (up 64%), with notable increases in grants to Iranian (up 1,603), Sudanese (up 1,018) and Eritrean nationals (up 947)
• 1,285 grants of an alternative form of leave (up 11%)
• 1,241 grants of Humanitarian Protection (down 4%) over half (695) of which were granted to Libyan nationals
• 5,612 people who were provided protection under resettlement schemes (down 3%), mainly Syrian nationals granted under the Vulnerable Persons Resettlement Scheme

Publications released on the same day that are related to this report include:

Provisional Long-Term International Migration (LTIM) estimates
Dataset | Released 27 February 2020
Estimates with confidence intervals for the year ending June 2019 are available. These include data on:

• immigration, emigration and net migration by citizenship over time in Table 1 and Chart 1TS
• immigration and emigration by reason for migration in Table 2 and Charts 2a and 2b
• immigration and emigration by reason for migration and citizenship in Table 3 and Charts 3a and 3b

Preliminary adjusted estimates are available in this dataset and have only been applied to LTIM estimates. The International Passenger Survey (IPS) estimates in Table 3 and Table 4 have not been adjusted.

International Passenger Survey (IPS), estimates by individual quarter
Dataset | Released 27 February 2020
Estimates of international migration, by individual quarter, up to Quarter 3 (July to Sept) 2019. These quarterly estimates can be derived from the IPS but are not fully processed survey data and as such are not official statistics. For more information regarding this decision, see International migration – terms, definitions and frequently asked questions.

Users should be cautious with any interpretation of individual quarter estimates, especially where the confidence interval is large in comparison with the estimate.

Home Office Immigration Statistics, year ending December 2019

Release | Released 27 February 2020
Includes both short- and long-term visas (including dependants) for non-EEA nationals and is available for the year ending December 2019. The release includes more detailed statistics by visa category, citizenship and industry sector. The release also includes data on citizenship, asylum and resettlement, detention, and returns.

National Insurance number allocations to adult overseas nationals: January 2002 to December 2019
Release | Released 27 February 2020
Includes both short- and long-term migrants for the year ending December 2019. The summary tables provide more detail by nationality and location of registrations in the UK.

Differences between the data sources are described in August 2019 progress report.

International migration – table of contents
Dataset | Updated 27 February 2020
Tool to locate the datasets for all Office for National Statistics (ONS) international migration outputs.

Long-term international migrant

The Office for National Statistics’ (ONS’s) migration statistics use the UN-recommended definition of a long-term international migrant: “A person who moves to a country other than that of his or her usual residence for a period of at least a year (12 months), so that the country of destination effectively becomes his or her new country of usual residence.”

EU citizenship groups

EU estimates exclude British citizens. The following EU citizenship groups are used:

• EU15: citizens of countries that were EU members prior to 2004, for example, France, Germany and Spain
• EU8: citizens of Central and Eastern European countries that joined the EU in 2004, for example, Poland
• EU2: citizens of Bulgaria and Romania, which became EU members in 2007. Between 2007 and 2013, these countries were subject to transitional controls restricting their access to the UK labour market; these restrictions were lifted on 1 January 2014

Home Office visa data are for non-EEA citizens. Non-EEA refers to citizens of countries outside the EU and excludes Iceland, Liechtenstein, Norway and Switzerland.

Work-related migration

In the International Passenger Survey (IPS), “Work-related” migration includes those people who migrate with a “Definite job” to go to already and those who migrate “Looking for work”.

Full details of the terms and definitions used by the ONS can be found in International migration: terms, definitions and frequently asked questions

The sources of data included in this release are not directly comparable. However, taken together, the different sources of data provide a better indication of trends than any single source alone. This approach is explained in the Report on international migration data sources: July 2018 and Understanding different migration sources: August 2019 progress report, which set out our latest understanding of the quality of International Passenger Survey (IPS) migration estimates.

Office for National Statistics (ONS) long-term international migration estimates

The main data source for estimates of long-term international migration is the IPS, which captures migrant intentions. We publish two types of estimates for long-term international migration: the IPS and Long-Term International Migration (LTIM) estimates.

LTIM estimates are based on IPS data but with the following adjustments:

• migrants not included in the IPS survey, such as asylum seekers and refugees, and migrants entering or leaving the UK across the un-surveyed land border with the Republic of Ireland
• migrants changing their intentions with regards to length of stay
• migrants with uncertain intentions (preliminary adjustments – see Section 14)

It is only possible to perform the LTIM adjustments described here for estimates by a single characteristic, such as citizenship or reason for migration. Where estimates involve more than one characteristic, such as estimates by citizenship and reason for migration, estimates are published that are based solely on the IPS data.

The Migration statistics first time user guide describes these data and the Long-Term International Migration estimates methodology details the method used to calculate LTIM estimates.

For more detailed information on our migration statistics methodology, please see International migration methodology.

ONS labour market estimates

We produce estimates of the labour market activity of the resident population in the UK by nationality and country of birth from the Labour Force Survey (LFS). Statistical significance testing is not available for the labour market EU and non-EU breakdowns.

A number of differences have been identified when making comparisons between migration data from the Annual Population Survey (APS), LFS and IPS. On 21 August 2019, we published a report outlining the findings from research into differences between these survey sources.

Home Office data

Home Office immigration statistics provide the numbers of people who are covered by the UK’s immigration control and related processes, based on a range of administrative and other data sources. Where direct comparisons are made to the IPS data, Home Office visa data are for main applicants only and for long-term visas (one year or more). The Home Office immigration statistics: user guide provides more detail.

The Migration research and analysis page brings together a range of statistical and research reports on migration published by the Home Office. This includes EU Settlement Scheme statistics, analysis on the exit checks programme and statistics on migrants’ visa and leave status.

Department for Work and Pensions (DWP) data

The DWP National Insurance number (NINo) statistics count the volume of NINos registered to adult non-UK nationals. Further information, including detail on data sources, uses and limitations of the series is provided in the background information.

Population and migration statistics transformation

The Government Statistical Service’s (GSS’s) population and migration statistics transformation programme is working towards putting administrative data at the core of international migration statistics. The transformation overview report provides the latest update on the transformation journey.

As part of this, we are transforming our migration statistics, making use of all available data to provide a richer and deeper understanding of migration. Since July 2018, we have been integrating outcomes from this work into the Migration Statistics Quarterly Report (MSQR).

We published our first set of preliminary adjustments in the August 2019 MSQR and have applied the same preliminary adjustments to the headline measures in this report to provide our best possible assessment of migration trends. The figures and trends in this report are therefore based on our adjusted estimates where available, which have so far been applied until 2016 for EU migration, and up to the latest year for non-EU migration. Our best assessment of EU net migration since 2016 remains our International Passenger Survey (IPS)-based estimates.

As other new data sources become available, we will continue to refine our adjustments further and reflect this in our migration statistics. We plan to develop the preliminary adjustments, and will inform users of these when possible, with final adjustments expected to be developed by summer 2020.

The International Passenger Survey (IPS) and the Long-Term International Migration (LTIM) estimates are currently the only sources of data to provide both long-term immigration and emigration, and so net migration estimates for the UK.

The IPS is a sample survey and as such provides estimates. When the estimates are broken down beyond the headline figures, they are subject to greater levels of uncertainty.

To ensure confidence in our estimates, we review all available data sources to make the best assessment of migration in the UK. For example, Home Office administrative data on non-EU citizens travelling are more detailed and do not have the known possible variability present in estimates made from sample surveys.

Accuracy of long-term migration estimates

Surveys gather information from a sample of people from a population as it is not possible to ask every person travelling in and out of the country to fill out a survey. This means we have to estimate total changes, which can be affected by the group of people we sample. We use confidence intervals to measure uncertainty around the estimate. Users are advised to be cautious when making inferences from estimates with relatively large confidence intervals.

Preliminary adjustments to LTIM estimates based on all available sources

To get the best overview of trends in migration, we need to look at all available data sources. To help us address the impact of uncertain intentions for non-EU students at the end of their studies, and for EU8 citizens moving to the UK, we have applied preliminary adjustments to our IPS-based estimates based on administrative data from the Home Office and from the Department for Work and Pensions (DWP). These tell us about people’s actual behaviour and help provide a fuller assessment of migration patterns.

For EU migration, our preliminary adjustment applies up to March 2016, drawing on the strengths of what DWP data tell us about National Insurance number (NINo) registrations by people born in EU8 countries. From 2016, we have seen some changes to the trends in net migration for EU countries, and so we are reviewing what further data sources can add evidence on which to base an adjustment after this point.

For non-EU migration, our preliminary adjustment applies from 2012 through to the latest quarter. This draws on the strengths of what Home Office data tell us about emigration of non-EU students.

The methods applied in the current preliminary adjustments are described in the Long-Term International Migration (LTIM) methodology guidance (section 4).

Revisions to the ONS migration estimates

Revisions to net migration estimates in light of the 2011 Census were made in April 2014. The report, a summary and guidance (PDF, 56KB) on how to use these revised figures are available.

Owing to an unusual pattern in student migration seen between the year ending September 2016 and the year ending September 2017, revisions were made in February 2019 to LTIM and IPS estimates for non-EU formal study immigration. A guidance note has been published to explain the revision. The revision affects estimates for the years ending September 2016, December 2016, March 2017 and June 2017. As non-EU student immigration feeds into overall immigration and net migration estimates, we have also produced revised estimates for these figures.

Imbalance and discontinuity work

The IPS has recently transferred outputs from data collected on paper forms to an improved method using tablet computers. Tablet data collection was phased in gradually from September 2017 to April 2018. More background information about the rollout is available.

The new tablets enable us to improve the quality of the IPS data collected. However, discontinuities (that is, step changes in the time series) arising from the introduction of tablet data collection in the IPS are possible. We have worked with academic experts and the Office for National Statistics (ONS) Methodology Team to produce a method for detecting any such discontinuities.

We have continued to monitor the results as more data have become available. Further analysis using a longer series of data is required to determine whether there are any discontinuities, so some caution is still advised in the interpretation of data in this release.

Methodological changes are planned to the estimates of international visitors in the IPS. These are weighting adjustments to address concerns about the imbalance (that is, large differences in numbers) in the IPS between the estimates of numbers of visitors arriving and departing, for some nationalities. The new method has been developed in consultation with users and methodological experts. We plan to implement the new method to the overseas travel and tourism statistics next year. A revised back series will also be published at this time. More information about the planned changes will be published as soon as possible.

Please note that while the imbalance work is unlikely to affect long-term migrants in the IPS, we have committed to exploring whether the survey processes that cause the imbalance in international visitor estimates also affect long-term migration further, as part of our Migration Statistics’ workplan to understand different migration data sources.

The changes in data collection methods and planned methodological changes were described in the Travel trends 2017: recent data collection changes and planned methodological changes article, in July 2018.

Quality and methodology

More quality and methodology information on strengths, limitations, appropriate uses, and how the data were created is available in the Long-Term International Migration QMI.

For more detailed information on our migration statistics methodology, please see International migration methodology.