The feature, which will be available beginning Monday, May 17, will only be available for people in England. It will also only be useful if the destination country recognizes the NHS application as valid proof the user has been vaccinated completely. Complete immunization means the user received both doses of the vaccine.

UK government to use NHS app as "passport"

The application was initially designed to allow users to message their physicians, request repeat prescriptions, book appointments and access their medical records. It is different from the NHS COVID-19, a contact tracing application for monitoring the spread of the pandemic in England and Wales.

On Wednesday, April 28, Transport Secretary Grant Shapps confirmed in an interview that they were working on an NHS application, the same one used for booking appointments, that would show that users have been vaccinated. Shapps added that he was working with partners worldwide to make sure that the new system will be recognized internationally "as that's the way forward."

Shapps noted that certification could take on a variety of formats. However, he emphasized that they always look to digital solutions first. As it stands, the NHS application will only be available to people with smartphones. People without access to smartphones are advised to coordinate with their general practitioners.