Peritoneal equilibration test (PET) is the gold standard for evaluating peritoneal transport, and measurement of the drain volume after 4‐h dwell time with glucose 4.25% is a simple means of evaluating failure of ultrafiltration. The study objective was to verify if the measurement of the volume drained after 4 h dwell of icodextrin at 7.5% (ICO), has a better correlation with the parameters of PET. Patients in a peritoneal dialysis program (N = 35) underwent three procedures: PET; determination of the drain volume after a 4‐h dwell with glucose 4.25%; and determination of the drain volume after a 4‐h dwell with ICO. Among patients who were classified as high transporters, the ultrafiltration volume was greater after ICO use. The ICO ultrafiltration volume correlated negatively with the ratio between the 4‐ and 0‐h dialysate glucose concentrations (D4/D0 ratio, r = −0.579; P = 0.002), correlating positively with the dialysate‐to‐plasma ratio for creatinine (D/PCr ratio, r = 0.474; P = 0.002). For ICO, the area under the receiver operating characteristic curve was 0.867 and 0.792 for the D/PCr and D4/D0 ratios (P < 0.0001 and P = 0.004, respectively), compared with 0.738 and 0.710 for glucose 4.25% (P = 0.020 and P = 0.041, respectively). A cut‐off volume of 141 mL discriminated high/high‐average transporters from low/low‐average transporters. Volume drained after ICO use better predicts peritoneal transport patterns than does that drained after the use of glucose 4.25%.