<p>Overactive bladder (OAB) is a commonly occurring condition in older adults that has significant consequences on health and quality of life. In later life, many older adults also live with frailty, a condition characterized by vulnerability to insult and associated with a lesser probability of a full recovery. Frail older adults comprise a distinct group of older adults, often living with complex comorbid disease. There is a bidirectional relationship between frailty and OAB, though causation has not been established. β₃-Adrenoreceptor agonists like mirabegron offer a pharmacological alternative over antimuscarinics, which may be associated with intolerable side effects in older patients. While mirabegron has demonstrated efficacy and tolerability in community-dwelling older adults, prospective studies on its use in frail older adults remain limited. Here, we review available evidence on use of mirabegron in older adults and frail older adults, including safety, tolerability and efficacy. Evidence suggests that mirabegron has favourable safety and side effect profiles, decreases OAB symptoms, and improves quality of life. Mirabegron remains an acceptable alternative to antimuscarinic treatment in older adults and frail older adults.</p>