Objectives Nocturnal haemodialysis (NHD), characterised by 8-hour sessions >= 3 times a week, is known to improve clinical parameters in the short term compared with conventional-schedule haemodialysis (HD), generally 3x3.5-4 hours a week. We studied long-term effects of NHD and used patients on conventional HD/haemodiafiltration (HDF) as controls. Design Four-year prospective follow-up of patients who switched to NHD; we compared patients with patients on HD/HDF using propensity score matching. Setting 28 Dutch dialysis centres. Participants We included 159 patients starting with NHD any time since 2004, aged 56.7 +/- 12.9 years, with median dialysis vintage 2.3 (0.9-5.1) years. We propensity-score matched 100 patients on NHD to 100 on HD/HDF. Primary and secondary outcome measures Control of hypertension (predialysis blood pressure, number of antihypertensives), phosphate (phosphate, number of phosphate binders), nutritional status and inflammation (albumin, C reactive protein and postdialysis weight) and anaemia (erythropoiesis-stimulating agent (ESA) resistance). Results Switching to NHD was associated with a nonsignificant reduction of antihypertensives compared with HD/HDE (OR Conclusions After switching to NHD, the lower need for antihypertensives, phosphate binders and ESA persists for at least 4 years. These sustained improvements in NHD contrast significantly with the course of these parameters during continued treatment with conventional-schedule HD and HOE. NHD provides an optimal form of dialysis, also suitable for patients expected to have a long waiting time for transplantation or those convicted to indefinite dialysis.