Institute of Epidemiology & Health Care



We enable research using the Office for National Statistics (ONS) Longitudinal Study - the largest nationally representative longitudinal dataset in the UK

Longitudinal studies follow the lives of individuals over a long period of time, showing us how people are affected by changes in society. The ONS Longitudinal Study contains the census data and some life events data of approximately one million sample members, collected over 40 years. This service is free to the user.

About the ONS Longitudinal Study

About the ONS Longitudinal Study

Find out more about the study

About the ONS Longitudinal Study

Using the ONS Longitudinal Study

Find out how to access and use the data

Data dictionary

Data dictionary

Look up the variables in the study

Celsius Resources


Information and guidance to help you use the data

Research at Celsius


Current and past LS projects and the outputs resulting from this research

About Celsius


Meet the team

Latest news

ONS in Pimlico safe setting reminder

Please note that to contact the CeLSIUS team when using LS data in ONS London, you need to phone 020 7592 8632 (8632 internally) or one of the other numbers displayed on the safe setting wall. This is because we are no longer on the Red Route, along which you are permitted to move; we must therefore escort you to our desks. You are encouraged not to let this deter you - we are always pleased to meet LS users face-to-face.

The First Annual UK Longitudinal Studies Research Conference:  April 8th - 9th 2019, Queen's University Belfast

The three UK census longitudinal studies are organising this conference to showcase their research and to build research capacity amongst existing and prospective users. The first day of the conference will present research findings from across the UK and set the UK experience in a wider context with an international panel. The second day will offer two parallel workshops. One strand will provide 'safe researcher training' to certify attendees to use longitudinal data across the UK. The second will be concerned with the development of research ideas and seeking research funding.  Please keep these dates free. A detailed programme will be announced in December 2018.

CeLSIUS Research Brief: Windrush migrants in the LS (PDF)

CeLSIUS estimate that in 2011 there were around 1,735 Windrush children who had entered the country prior to 1971 - find out more about how the ONS LS can be used to estimate the number of Windrush migrants in ways which go beyond the methods based solely on the most recent census, or on the Labour Force Survey.

Webinar: Geography and longitudinal data - the UK Household Longitudinal Study and the UK Longitudinal Studies, held on 11th July 2018

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