During the first wave of the Covid-19 pandemic, access to health care was limited, and patients encountered important delays for scheduled appointments and care. Empirical data relying on patients' reports of forgoing health care are scarce. This study investigated Covid-19-related self-reports of forgoing health care in a sample of vulnerable outpatients in Geneva, Switzerland. We collected data from 1167 adult outpatients, including clinically vulnerable patients (with chronic diseases), geriatric patients (involved in a health care network for people aged 60 or older), and socially vulnerable patients (involved in a migrant health program or a mobile outpatient community care center) in June 2020. Data on sociodemographic factors, forgoing health care, and anti-SARS-CoV-2 antibodies were collected. Of the patients, 38.5% reported forgoing health care. Forgoing health care was more frequent for younger patients, women, patients with a low level of education, and patients with a chronic disease (p < .001). There was no significant association between the presence of anti-SARS-CoV-2 antibodies and forgoing health care (p = .983). As the decrease in routine management of patients might have important and unpredictable adverse health consequences, avoiding delayed health care is crucial.