Aim: To assess the cost-effectiveness of nutrition education by dedicated dietitians (DD) for hyperphosphatemia management among hemodialysis patients.Materials and methods: This was a trial-based economic evaluation in 12 Lebanese hospital-based units. In total, 545 prevalent patients were cluster randomized to DD, trained hospital dietitian (THD), and existing practice (EP) groups. During Phase I (6 months), DD (n = 116) received intensive education by DD trained on renal nutrition, THD (n = 299) received care from trained hospital dietitians, and EP (n = 130) received usual care from untrained hospital dietitians. Patients were followed-up during Phase II (6 months).Results: At baseline, EP had the lowest weekly hemodialysis time, and DD had the highest serum phosphorus and malnutrition-inflammation score. The additional costs of the intervention were low compared with the societal costs (DD: $76.7, $21,007.7; EP: $4.6, $18,675.4; THD: $17.4, $20,078.6, respectively). Between Phases I and II, DD showed the greatest decline in services use and societal costs (DD: –$2,364.0; EP: –$1,727.7; THD: –$1,105.7). At endline, DD experienced the highest decrease in adjusted serum phosphorus (DD: –0.32; EP: +0.16; THD: +0.04 mg/dL), no difference in quality-adjusted life-years (QALY), and the highest societal costs. DD had a cost-effectiveness ratio of $7,853.6 per 1 mg decrease in phosphorus, compared with EP; and was dominated by THD. Regarding QALY, DD was dominated by EP and THD. The results were sensitive to changes in key parameters.Limitations: The analysis depended on numerous assumptions. Interpreting the results is limited by the significant baseline differences in key parameters, suggestive of higher baseline societal costs in DD.Conclusions: DD yielded the greatest effectiveness and decrease in societal costs, but did not affect QALY. Regarding serum phosphorus, DD was likely to be cost-effective compared with EP, but had a low cost-effectiveness probability compared with THD. Regarding QALY, DD was not likely to be cost-effective. Assessing the long-term cost-effectiveness of DD, on similar groups, is recommended.