Aim: The aim of this study was to evaluate and compare the sealing ability of three obturating materials used with single-cone technique: C Point/Endosequence BC sealer, gutta-percha/Endoseal MTA and gutta-percha/GuttaFlow bioseal using bacterial leakage model with Enterococcus faecalis. Materials and Methods: Seventy-six extracted human single-rooted mandibular premolars with straight canals prepared using Hyflex CM up to 45/04 and assigned to 3 experimental groups according to the root canal filling material as Group A - C Point/Endosequence BC sealer; Group B - guttapercha/Endoseal MTA; Group C - guttapercha/GuttaFlow bioseal. Split-chamber bacterial leakage model was prepared and microleakage analysis was made every 24 h for up to 9 weeks. The presence of E. faecalis was confirmed by light microscopy and Gram staining. Results: A survival analysis was performed using Kaplan–Meier plots and a log-rank test and it was found that Group A showed the best apical seal followed by Group C and then Group B at the end of the observational period. The difference in bacterial leakage among Group A and C versus Group B was statistically significant (P < 0.05), but there was no significant difference between Group A and Group C. Conclusion: C Point/Endosequence BC sealer and GP/Guttaflow bioseal sealer has shown better apical seal with single-cone technique as compared to GP/Endoseal MTA.