Introduction: Intradialytic hypotension remains the commonest complication of outpatient haemodialysis (HD) treatments. On-line haemodiafiltration (HDF) has been reported to reduce the frequency of intradialytic hypotension. We introduced on-line HDF into our satellite dialysis program, and prospectively audited the effect of HDF on cardiovascular stability. Methods: 34 patients’ dialysis schedules (Tuesday/Thursday/Saturday) were converted to online post-dilutional HDF, and 44 patients’ dialysis schedules (Monday/Wednesday/Friday) remained on high-flux HD. Blood pressure and intra-treatment complications were monitored prospectively for 12 months. Results: There was no significant change in pre-treatment mean arterial blood pressure in the HDF group during the 12 months of the study (pre-treatment 113.7 ± 0.7 mm Hg vs. 109.3 ± 2.8 after 12 months), or for the HD cohort (113.9 ± 2.7 vs. 117.9 ± 2.6). However, the frequency of intradialytic hypotensive episodes was greater for the HDF cohort: 25.9 versus 16.5% in the HD cohort, p = 0.0116. During HDF, on average >16 litres of substitution fluid was used and the median temperature was 36°C (35°C–36°C), higher than the dialysate in the HD cohort which was 35°C (35°C–36°C), p < 0.05. Conclusion: In this study, HDF did not improve blood pressure control or reduce the frequency of intradialytic hypotensive episodes compared to high-flux HD using cooled dialysate.