Health campaigners plan to protest outside the annual general meeting of Barts Health NHS Trust on Wednesday of next week.
The east London hospitals trust is making up to 100 enquiries a week to the Home Office about patients.
This involves sharing patients’ information with immigration officials. The Home Office could then use the details to deport or detain migrants.
Barts Health took part in a pilot of 20 trusts checking patients’ passports.
The pilot ended last October, but the trust is continuing the practice.
Many migrants from outside the European Union are not entitled to free health care under the Tories’ “hostile environment” policy.
The lobby outside Mile End hospital has been organised by the North East London Save Our NHS group.
An open letter launched by the campaign calls on Barts Health to “stop asking patients for ID, suspend upfront charging and stop collaborating with the hostile environment”.