Background and Aims: Subarachnoid block using short-acting drugs like chloroprocaine may be preferred in ambulatory surgeries. Various adjuncts are being added to local anesthetics to enhance the quality of analgesia. Fentanyl given by intrathecal route with local anesthetics has antinociceptive and synergistic effect. Our study aimed to elucidate the effects of adding fentanyl to 1% 2-chloroprocaine on duration of sensory block and analgesia for subarachnoid block. Methods: A prospective, randomized, double-blind study was conducted on a hundred patients of ASA physical status I/II, age group 18–80 years scheduled for elective infra-umbilical surgeries. Patients were allocated into two groups of 50 each to receive either 5 ml (50 mg) of chloroprocaine with 0.5 ml of normal saline (Group A) or 5 ml (50 mg) of chloroprocaine with 0.5 ml of fentanyl 25 µg (Group B). Block characteristics, duration of analgesia and complications were assessed. Results: Sensory and motor block were achieved faster in chloroprocaine-fentanyl group. Duration of sensory and motor block, analgesia and return of voiding function, were significantly prolonged in Group B. No difference was noted in maximum motor block and ambulation time. Eight patients in Group B developed pruritus. Chi-Square and Student’s unpaired t-test were used to analyse results, using Epi info version 7.2.1.0 statistical software. Conclusion: Isobaric chloroprocaine and fentanyl mixture enhanced the duration of sensory block, analgesia and motor block without increasing ambulation time but with delay in return of voiding reflex.