AimsTo analyse the changes in erythropoietic and estimated fluid volume parameters after the initiation of ipragliflozin, a sodium‐glucose co‐transporter 2 inhibitor, in patients with type 2 diabetes mellitus (T2DM) and chronic kidney disease (CKD).MethodsThis was a post‐hoc analysis of the PROCEED trial, which evaluated the effect of 24‐week ipragliflozin treatment on endothelial dysfunction in patients with T2DM and CKD. We evaluated the changes in erythropoietic and estimated fluid volume parameters from baseline to 24 weeks post‐treatment in 53 patients who received ipragliflozin (ipragliflozin group) and 55 patients with T2DM and CKD without sodium‐glucose co‐transporter 2 inhibitors (control group), a full analysis set of the PROCEED trial.ResultsThe increases in haemoglobin [estimated group difference, 0.5 g/dl; 95% confidence interval (CI), 0.3‐0.8; p < .001], haematocrit (estimated group difference, 2.2%; 95% CI, 1.3‐3.1; p < .001) and erythropoietin (estimated log‐transformed group difference, 0.1; 95% CI, 0.01‐0.3; p = .036) were significantly greater in the ipragliflozin group than those in the control group. Ipragliflozin treatment was significantly associated with an increase in erythropoietin, independent of the corresponding change in haemoglobin (β = 0.253, p < .001) or haematocrit (β = 0.278, p < .001). Reductions in estimated plasma volume (estimated group difference, −7.94%; 95% CI, −11.6 to −4.26%; p < .001) and estimated extracellular volume (estimated group difference, −181.6 ml; 95% CI, −275.7 to −87.48 ml; p < .001) were significantly greater in the ipragliflozin group than those in the control group.ConclusionsErythropoiesis was enhanced and estimated fluid volumes were reduced by ipragliflozin in patients with T2DM and CKD.Clinical trialPROCEED trial (registration number: jRCTs071190054).