Timely presentation to care for people newly diagnosed with HIV is critical to optimize health outcomes and reduce onward HIV transmission. Studies describing presentation to care following diagnosis during a hospital admission are lacking. We sought to assess the timeliness of presentation to care and to identify factors associated with delayed presentation. We conducted a population-level study using health administrative databases. Participants were all individuals older than 16 and newly diagnosed with HIV during hospital admission in Ontario, Canada, between April 1, 2007 and March 31, 2015. We used modified Poisson regression models to derive relative risk ratios for the association between sociodemographic and clinical variables and the presentation to out-patient HIV care by 90 days following hospital discharge. Among 372 patients who received a primary HIV diagnosis in hospital, 83.6% presented to care by 90 days. Following multivariable analysis, we did not find associations between patient sociodemographic or clinical characteristics and presentation to care by 90 days. In a secondary analysis of 483 patients diagnosed during hospitalization but for whom HIV was not recorded as the principal reason for admission, 73.1% presented to care by 90 days. Following multivariable adjustment, we found immigrants from countries with generalized HIV epidemics (RR 1.265, 95% CI 1.133-1.413) were more likely to present to care, whereas timely presentation was less likely for people with a mental health diagnosis (RR 0.817, 95% CI 0.742-0.898) and women (RR 0.748, 95% CI 0.559-1.001). Future work should evaluate mechanisms to facilitate presentation to care among these populations.