Annual Survey of Hours and Earnings linked to Migrant Workers Scan - England, Scotland and Wales

The Migrant Workers Scan is a standalone, but fully linkable, dataset based on the 1% sample of individuals included in the Annual Survey of Hours and Earnings (ASHE).

The Migrant Workers Scan contains information on overseas nationals who have registered for, and been allocated, a National Insurance Number. The data is held by HM Revenue and Customs (HMRC) and delivered annually by the Department for Work and Pensions to the Office for National Statistics (ONS). The Migrant Workers Scan began recording migration information in 1975, though its current structure has been in place since 2002 (earlier records are compiled from predecessor systems). Arrivals prior to 1975 are not captured.

In addition to ASHE, the Migrant Workers Scan can also be directly linked to other datasets curated by the Wage and Employment Dynamics team, including Enriched-ASHE and HMRC’s Pay-As-You-Earn (PAYE) and Self-Assessment (SA) data, which holds records for the same 1% of the working population.

By linking the Migrant Workers Scan to ASHE and other datasets, researchers gain a far richer understanding of migrants’ role in the UK labour market. The Migrant Workers Scan provides nationality and immigration details that, when combined with detailed pay, occupation and employment histories, reveal a fuller picture of migrants’ work and earnings.

This linkage enables analysis of wage progression, job mobility and sectoral participation, as well as offering rare insights into self-employment. It also opens the door to exploring regional and occupational patterns, identifying wage gaps and assessing the wider contribution of migrants across the economy. In short, the linked data moves us from partial snapshots to a more complete view of migrant employment, helping policymakers and researchers to better evidence both the challenges and the vital contributions of migrant workers.

This dataset was developed as part of the Wage and Employment Dynamics project to aid better understanding of wage inequalities in Britain.

Component datasets and linkage

The Migrant Workers Scan dataset contains de-identified personal information, including date of arrival in the UK, date of National Insurance Number registration, nationality, and country of residence immediately prior to arrival. It also records age, marital status, and postcode area at registration, along with index fields that enable linkage to ASHE and other datasets. The ASHE dataset includes de-identified personal information such as age, gender, employment information (such as wage and working hours), and employer information (work location identifier).

Examples of research questions

• What are the earnings differences between migrant and UK-born workers across occupations, industries and regions?
• How do wage trajectories differ for recent migrants compared to long-settled migrants and UK-born workers?
• Do migrants transition into higher-skilled or higher-paying roles over time, or are they more likely to remain in entry-level jobs?
• Are migrant workers more likely to experience pay penalties or limited progression compared to similar UK-born workers?

This list is illustrative only and intended to demonstrate the research potential of the dataset. For research priorities, please see the areas of research interest database and priority research questions for ASHE linked to Migrant Workers Scan.

Other supporting resources

Accessing the data

Accredited researchers with an approved project can access the Migrant Workers Scan dataset via the ONS Secure Research Service. 

1. Apply to become an accredited researcher under the Digital Economy Act 2017

• Apply for researcher accreditation through the People & Projects Service: How to access: Apply for researcher accreditation.

2. Apply for an accredited research project

• More information about the dataset will be available soon on the ADR UK Data Catalogue.
• Submit an application to the Project Accreditation Service for SRS: Apply for an accredited research project – ONS.

3. Access the data securely

The options available to access this dataset are:

• Safe Rooms – based in ONS offices in Titchfield and Newport, open Monday-Friday, 9.00-16.00
• SafePod Network– a small, self-contained secure room with a single workstation
• Assured Organisational Connectivity – the ability to access the ONS Secure Research Service from your office or home. Check what arrangements your institution already has or can put in place.