Overview

Origin-destination data show the movement of people from one location to another. They are sometimes known as flow data.

This information can help local and central government plan and fund infrastructure for:

  • education

  • healthcare

  • housing

  • transport

Origin-destination data is also used to analyse population movement trends for migration and commuting patterns.

Levels of access and geography

We will provide origin-destination data as:

  • standalone flows, containing no characteristics

  • univariate datasets, about one characteristic

  • multivariate datasets, about two or more characteristics

We will classify these data in three ways.

Public

The public data will mostly be standalone flows and univariate datasets. We aim to release these at local authority level. We are assessing if we can produce some of these at lower geographic levels, such as Middle Layer Super Output Area (MSOA) or workplace zone.  We are also considering whether we can release some of the multivariate datasets publicly. 

Safeguarded

Safeguarded data will contain more detail than the public datasets. They will be released as univariate and multivariate datasets.  We aim to release the majority of these down to MSOA level.  We may only be able to provide data at local authority level where the safeguarded data contains more detailed characteristics.  We will only make safeguarded data available to data analysts, under certain terms and conditions. The UK Data Service is likely to hold safeguarded data in line with previous censuses.

Secure

Secure data contains the most detailed origin-destination data. They will be released in univariate and multivariate datasets. We aim to release these down to Output Area (OA) level and workplace zones. These data are stored in the Office for National Statistics' (ONS) Secure Research Service (SRS) and only available to approved or accredited researchers. Learn more about accessing secure data.

We may change our plans for the public, safeguarded and secure origin-destination data to protect confidentiality. For example, we may:

  • reduce the level of detail we provide for some characteristics

  • reduce the geographical detail we provide

  • move datasets to a more secure setting

Types of origin-destination data

We plan to release four types of origin-destination data.

Migration flow data

Migration flow data shows the national and international migration of residents with a different address during the year before Census Day. We aim to provide public migration flow datasets by:

  • age

  • economic activity

  • ethnic group

  • general health

  • National Statistics Socio-Economic Classification (NSSEC)

  • passport held

  • tenure

We are likely to only provide migration flow data by industry in our safeguarded environment and by occupation in our secure environment.

Census 2021 took place during the coronavirus (COVID-19) pandemic, where various travel restrictions including lockdowns were in place from March 2020. As a result, there was less international migration into the UK. To protect confidentiality, our public and safeguarded migration flow datasets will contain less detail on country of origin for international migrants, than we provided for 2011.

Workplace flow data

Workplace flow data represent usual residents aged 16 and over who were working in the week before the census. They show the location of workplaces in relation to an individual's usual residence. A few of the datasets also consider work-related second addresses.

We plan to publish public workplace flow datasets by:

  • age

  • approximated social grade

  • car or van availability

  • ethnic group

  • hours worked

  • method of transport

  • NSSEC

  • passport held

  • sex

In our safeguarded environments, we plan to provide datasets on:

  • age, sex and method of transport

  • ethnic group

  • family status

  • industry

  • occupation

In our secure environment, we will provide more detailed multivariate datasets for output areas. We will use both student employment status and characteristics used in the public and safeguarded data. Student employment status enables full-time students to be identified separately and remaining persons are classed as either in full-time or part-time employment. 

Second address flow data

Second address flow data show the location of people's second addresses and how far they are from their usual residence or workplace. Second address flow data will only be available for England and Wales, as Northern Ireland and Scotland did not collect this information.

We plan to publish these standalone flows publicly:

  • usual residence to workplace, for people with a work-related second address

  • second address to workplace, for people with a work-related second address

  • usual residence to second address

  • usual residence to second address, for dependent children with a second parental address

We will consider whether we can share publicly usual residence to second address flows, by age.

In our safeguarded environments, we are likely to provide univariate datasets on:

  • economic activity

  • ethnic group

  • NSSEC

  • passport held

  • second address type

In our secure environment, we will provide more detailed multivariate datasets using combinations of the characteristics included in the public and safeguarded datasets, along with tenure and family status.

Student flow data

Student flow data show migration patterns of individuals living at student term-time or boarding school addresses in the UK one year before Census Day. These people may not necessarily have been students at the time of Census 2021.  As such, student flow data:

  • includes graduates who migrated from a UK term-time address in the year before census

  • collectively includes home, EU and international students who migrated from a UK student term-time address in the year before census

  • does not include first year university students who lived at a parental address a year before census

  • does not include international students who lived outside the UK in the year before census

We aim to publish public datasets on student flow data by:

  • age

  • ethnic group

  • passport held

  • NSSEC

In our safeguarded environments, we are likely to provide datasets on:

  • Age, sex and student status

  • economic activity

In our secure environment, we will provide more detailed multivariate datasets by student status and combinations of the characteristics included in the public data, as well as tenure. Student status enables full-time and part-time students to be identified.

Release plans

We will begin releasing origin-destination data during phase three of the Census 2021 outputs release schedule. We plan to release public origin-destination datasets first, then follow these with the more complex safeguarded and secure datasets.

Changes to UK origin-destination data

England, Wales and Northern Ireland held their censuses in March 2021 and Scotland held their census in March 2022. The difference in dates mean we are unable to combine these data to produce a single reliable set of UK origin-destination datasets.  

Instead, we hope to combine origin-destination data for England, Wales and Northern Ireland. Where it is not possible to do this, we will produce datasets for England and Wales only.

The datasets we plan to produce will include the following Scottish flows:

  • to Scotland, where a usual resident of England, Wales or Northern Ireland worked in Scotland

  • from Scotland, where a usual resident of England, Wales or Northern Ireland had an address in Scotland one year prior to Census Day

  • to Scotland, where a usual resident of England and Wales had a second address in Scotland

The Scottish geographies, based on Scotland's census in 2022, are unlikely to be available at the time we produce origin-destination datasets. Therefore, we plan to provide our initial origin-destination datasets at higher level Scottish geographies, which are not set to change. Once the more detailed Scottish geographies become available, we will investigate how feasible it is to incorporate these into our origin-destination datasets.

Where possible and for comparability, we aim to harmonise datasets and output classifications across the UK and with 2011.

New considerations for Census 2021

We are in a period of significant economic and societal change. This change is not only because of the coronavirus (COVID-19) pandemic.

The effect these factors may have had on origin-destination outputs include:

  • fewer people entering the country in the year prior to Census Day, as a result of international travel restrictions and smaller numbers of people migrating internally

  • fewer people commuting to work, with the method of transport also affected because of advice to avoid public transport and work at home where possible

  • more people working from home

  • students potentially leaving their term-time address to live at home while studying remotely

  • travel restrictions on international students, however, EU students may have migrated to the UK when possible, to gain EU settlement status

  • individuals with a second address potentially deciding to make their second address their usual address

Working with others

We are working with a range of stakeholders through our origin-destination working group to design, create, store and disseminate Census 2021 origin-destination products. We aim to produce Census 2021 origin-destination products in timely manner that meet our users' needs as far as possible. 

Internal members include topic experts on:

  • migration

  • travel to work

  • demography and census transformation

  • population estimates

  • statistical disclosure control

External members include:

  • National Records of Scotland (NRS)

  • Northern Ireland Statistics and Research Agency (NISRA)

  • Welsh Government

  • Department for Transport

  • UK Data Service

  • local authorities

  • academia and commercial research, including transport planning

More information

If you have questions about origin-destination data or are interested in joining our working group, please email census.outputs@ons.gov.uk.