OBJECTIVES To assess the cost–utility of erythropoiesis-stimulating agents (ESAs) in conjunction with red blood cell transfusions (RBCTs) in patients with cancer-treatment induced anaemia (CIA). METHODS A cost–utility analysis from an NHS and personal social services perspective was conducted by developing an ad hoc economic model. A lifetime time horizon was used and outcomes were discounted at 3.5% per annum. All ESAs were assumed to have the same clinical effectiveness. Haemoglobin (Hb) levels were assumed to drive health-related quality of life (HRQoL), with haemoglobin linearly mapped to utility. This was used to calculate incremental quality-adjusted life years (QALYs) while ESAs were administered and during a Hb “normalisation period” following cancer treatment. Incremental long-term QALYs were accrued solely through extrapolated overall survival. Short-term mortality and HRQoL associated with adverse events and RBCTs were not modelled. Costs included: ESA acquisition (list prices, British National Formulary) and administration, RBCT, additional blood tests with ESA therapy, and adverse event costs. RESULTS All ESAs except epoetin beta and darbepoetin alfa were cost-effective versus using RBCT only at an upper cost-effectiveness threshold of £30,000/QALY. Incremental cost-effectiveness ratios (ICERs) ranged from £19,400/QALY (biosimilar epoetin alfa) to £35,000/QALY (epoetin beta). Probabilistic sensitivity analysis showed that biosimilar epoetin alfa was cost-effective at the lower cost-effectiveness threshold of £20,000/QALY in 50.9% of simulations. In 19.5% of simulations it was clinically effective but not cost-effective and in 31.4% of simulations it was dominated by RBCT only. Additional sensitivity analyses demonstrated that overall survival was one of the most influential and uncertain parameters. When the survival advantage of ESAs (not statistically significant) was removed, the ICERs for all ESAs were over £100,000/QALY. CONCLUSIONS There is substantial uncertainty regarding the impact of ESA therapy on overall survival, which leads to significant uncertainty about the cost-effectiveness of ESAs in CIA.