Age-related immune dysfunction might impair the efficacy of immune checkpoint inhibitors (ICIs) in older patients. We aimed to evaluate the impact of age on clinical outcomes and tolerance of ICIs in a real-life setting.All patients receiving a single-agent ICI (cytotoxic T-lymphocyte-associated protein 4 [CTLA-4] or programmed death(ligand)1 [PD(L)-1] inhibitors) for the standard treatment of a locally advanced or metastatic cancer were included in this retrospective multicentric series. The primary end-point was overall survival (OS). Progression-free survival (PFS) and immune-related adverse events (irAEs) were secondary end-points. The impact of age was assessed using the threshold of 70 years.A total of 410 patients were included, for 435 lines of treatment, including 150 lines (34%) given to patients aged 70 years or older. The primary tumour types were lung cancer (n = 304, 74%), melanoma (n = 79, 19%) and urologic cancer (n = 27, 7%). Most of the administered treatments were PD(L)-1 inhibitors (n = 356, 82%). Median follow-up reached 46 months in the CTLA-4 cohort, and 20 months in the PD(L)-1 cohort. In both treatment cohorts, age did not impact OS (respectively, HR = 0.82, 95% CI 0.5-1.4; log-rank P = 0.49 and HR = 0.9, 95% CI 0.7-1.1; log-rank P = 0.27) or PFS (HR = 0.7, 95% CI 0.4-1.1; log-rank P = 0.13 and HR = 0.9, 95% CI 0.7-1.1; log-rank P = 0.19). Grade 3-4 irAEs rates were not statistically different between older and younger patients (11% vs 12%, P = 0.87).In a large real-world series of patients treated by ICI monotherapy, the long-term clinical outcomes were not statistically different between older or younger patients, with no increased immune-related toxicity.