Background Marginalised groups such as homeless people and migrants experience barriers to registration with a general practitioner (GP). While various interventions have been trialed to improve registration rates, the potential for opportunistic interventions through the ambulance service has not yet been considered. The aim of this study was to determine the scope for these interventions by researching the prevalence of GP registration amongst the homeless population that present to a regional English ambulance service that covers both rural and urban areas.

Methods A retrospective search of electronic patient records was carried out for cases where a box for the attending clinician to click to indicate homelessness had been ticked between 1st April 2016 and 30th September 2019. A search of these records for GP registration was then performed.

Results A total of 14 707 ambulance attendances were marked as being for a homeless patient. 10 511 (71.5%) had a GP recorded, while 4 196 (28.5%) did not. On average, the ambulance service had face-to-face contact with 11.5 homeless patients per day, and 3 face-to-face contacts with patients who did not have GP registration per day.

Conclusion This indicates ambulance services could perform opportunistic interventions to improve GP registration rates amongst the homeless population. The data also suggests that the ambulance service is well-placed to perform other opportunistic interventions targeted at the homeless population.