PURPOSE: To compare the efficacy and safety between half-dose photodynamic therapy (PDT) and eplerenone therapy for treating chronic central serous chorioretinopathy (cCSC). DESIGN: This was a multicenter, open-label, randomized controlled trial. METHODS: This investigator-initiated trial was conducted in 3 academic medical centers in the Netherlands. Eligible patients were randomized at a 1:1 ratio to receive either indocyanine green angiography-guided half-dose PDT or oral eplerenone for 12 weeks. Both anatomical and functional outcomes were evaluated at 3 months after the start of treatment. RESULTS: A total of 107 patients were randomly assigned to receive either half-dose PDT (n = 53) or eplerenone treatment (n = 54). Thirteen patients (3 in the PDT group and 10 in the eplerenone group) did not adhere to the study protocol. At the 3-month evaluation visit, 78% of patients in the PDT group had complete resolution of subretinal fluid accumulation compared to only 17% of patients in the eplerenone group (P < .001). Mean best-corrected visual acuity in Early Treatment of Diabetic Retinopathy Study letters at the 3-month evaluation visit was 83.7 ± 10.8 and 82.8 ± 9.0 in the PDT and eplerenone groups, respectively (P = .555). In addition, mean retinal sensitivity on microperimetry was 25.4 ± 3.4 dB and 23.9 ± 4.0 dB in the PDT and eplerenone groups, respectively (P = .041). Finally, mean vision-related quality of life scores were 87.2 ± 8.5 and 83.8 ± 12.1 in the PDT and eplerenone groups, respectively (P = .094). Three patients (6%) in the PDT group experienced adverse events during the study compared to 18 patients (33%) in the eplerenone group. CONCLUSIONS: Half-dose PDT is superior to oral eplerenone for cCSC with respect to both short-term safety and efficacy outcomes.