Objective: To evaluate cost-utility of sevelamer versus calcium-based phosphate binders (CaPB) in different patient cohorts and for different dialysis modalities. Methods: Systematic literature review was conducted with only studies reporting mortality considered. Subgroup analyses were carried out based on results from one trial (DCOR). Costs of dialysis were obtained from a recent UK-based study; dosage of drugs was taken from the DCOR trial, and unit prices from the British National Formulary; costs were expressed in £2007; utilities were sourced from the literature. Markov model was developed for analysis. Results: Six RCTs of sevelamer versus CaPB reporting all-cause mortality were identified. No significance was found in meta-analysis: RR=0.83 [95%CI:0.56-1.17]; difference in cardiovascular mortality was not significant, based on three RCTs: 0.94 [0.76-1.17]. In the general haemodialysed population sevelamer cost £6491 more than CaPB after ten years of treatment, regardless of dialysis modality. In the 65 and older population, cost of sevelamer was £30,293 higher, while efficacy was 0.52 QALYs greater; ICER=£58,405. In patients on peritoneal dialysis, sevelamer cost £17,837 more than CaPB, with identical efficacy; ICER=£34,389. In patients treated for at least two years, sevelamer cost £27,266 more, while its efficacy was 0.41 QALYs higher; ICER=£65,782. In the 65+ population treated for at least two years, cost of sevelamer was £38,378 higher, while efficacy was 0.70 QALYs greater; ICER=£55,182. Acceptability curves revealed that probability of sevelamer being cost-effective at £20,000/QALY ranged 1.2-13.4%; EVPI was £17-194. With the costs of dialysis excluded, ICER ranged from £11,944 to £22,543; for all scenarios ICER diminished with longer time horizons. Conclusion: Sevelamer is not likely cost-effective, but in the older population it is more cost-effective in patients on peritoneal dialysis than on haemodialysis. ICER is relatively high for subgroups, mainly due to the high cost of dialysis of patients who live longer due to sevelamer.