2011 Census Flow Data

The Data

Origin and destination tables are produced for the UK by the Census Offices, in 2011 there are four datasets:

  1. Travel to work (SWS) (origin: usual residence | destination: address of workplace)
  2. Migration (SMS) (origin: address one year ago | destination: usual residence )
  3. Second Residence (SRS) (origin: usual residence | destination: 2nd address residence)
  4. Student Residence (SSS) (origin: usual residence | destination: student address one year ago)

The layouts for these tables can be found on the ONS website.


For disclosure control purposes ONS have released the data under three levels of licence.

1. Public – open and accessible like any other Census data and downloadable in a SASPAC format from here.

2. Safeguarded – available to public and academic users to download in a SASPAC format from the UK Data Service. Please see our guidance note on the process users will have to go through to download the data and the terms and conditions.

3. Secure – available within the ONS Virtual Microdata Laboratory (VML) to Approved Researchers for specific projects. The data is available for interrogation using SASPAC in this environment.

Please see our guidance note (.pdf) on how to access data via these channels.

Data contained in more complex tables and for smaller geographies will only be available via the Safeguarded or Secure routes. An indication of the number of tables available at each level can be seen below and a list of tables currently published is here (.xls Jan 2016).



To help users access these tables there are number of support tools available:

  • SASPAC training courses: 1 day courses are available at City Hall (or on location) on a regular basis. An overview can be seen here (.pdf) and dates here. All the training materials including videos can be found on our training page.
  • Flow data training module (.pdf) contains background information on the data and step by step instructions on how to extract data using SASPAC.
  • Gazetteer complier tool: the ability to aggregate small area data into larger zones is a particularly valuable tool when working with origin-destination datasets. In order to help users complete rezoning tasks we have created a bank of 63 Gazetteer Files. The files can be used to rezone standard geographies in the UK. In addition we have also created an Excel-based tool (5MB .zip) which allows users to combine these files to create their own UK-wide gazetteer files.
  • ONS have also released their own user guide (.pdf) and a specific quality report (.pdf) relating to issues with the workplace (SWS) tables.

Alternatively, if you have any issues/queries relating to these datasets please contact the helpdesk.

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