Skip to main content

Data for contact tracing Your data and privacy

For contact tracing to work, the NHS COVID-19 app uses technology developed by Apple and Google called ‘exposure notification’ and ‘exposure logging’. This technology allows the app to send you alerts, using random IDs, when you've been near another app user who tests positive for coronavirus (COVID-19).

This technology has been developed to find people you've been near while protecting your privacy and identity.

The app uses this data to work out:

  • how much time you may have spent near another app user
  • how near you were to other app users during this time

The app uses the strength of the Bluetooth signal to work out how near app users are to each other. This data will remain only on your phone. It cannot be seen or used by anyone, unless you choose to share it.

If you test positive for coronavirus, you will be asked if you want to share this data. Without ever sharing who you are, we can alert other app users that they are at risk of coronavirus because they’ve spent time near someone who has tested positive. If you've been in close contact with users of the Scotland, Northern Ireland, Jersey or Gibraltar contact tracing apps, these users will also be alerted that they’re at risk of coronavirus. This is done using the same technology that alerts NHS COVID-19 app users in England and Wales.

Read more about what data the NHS COVID-19 app uses.