Chronic idiopathic/spontaneous urticaria (CIU/CSU) is a dermatological condition characterized by itchy wheals and/or angioedema of continuous or intermittent duration of ≥6 weeks with a high burden of disease and impact on quality of life. Omalizumab is a recombinant humanized monoclonal antibody that inhibits the binding of IgE to high affinity receptors, and is approved for the CIU/CSU indication. The objective of this systematic review was to evaluate and synthesize the evidence on the real-world effectiveness of omalizumab in CIU/CSU in daily clinical practice. Areas covered: This review of 84 observational effectiveness studies covers treatments (dosing, medication use), clinical outcomes (treatment response, disease activity, quality of life), and safety. Expert opinion: The clinical outcomes observed across studies underscore the real-world effectiveness of omalizumab in the management of CIU/CSU. Continued treatment may assist patients showing an initial response to achieve a complete treatment response. Response rates are aligned with observed changes in disease activity, symptom experience, and quality of life, and this across subtypes of CIU/CSU. The positive therapeutic profile is complemented by a positive safety profile. The real-world evidence summarized here points convincingly at the high degree of effectiveness of omalizumab in the treatment of CIU/CSU in daily clinical practice.