Heat exchangers heavily rely on the flow channels as a key design aspect, making the optimization of flow channel design of paramount importance. Whenever reduced thermal resistance is desired, straight fins may be provided on the tube surface. However, in this comprehensive 3D computational study, the implementation of helical fins is thoroughly examined to further enhance the thermo-hydraulic performance of the system. In the pursuit of optimal designs, the fin pitch and helix angle are varied while keeping fixed operating conditions. The helix angle is varied from 5° to 25° with a step size of 5°, while the fin pitch spans from 1/5 to 1/30. Two different type of fin shapes, i.e., concave and convex, are considered. The results indicate that the helical fins offer substantial improvements in the thermal performance of the system. The study reveals that the thermal conductance significantly increases with the helix angle, showing a maximum enhancement of 754% and 806% for concave and convex fin geometries, respectively. Furthermore, the study indicates that increasing the fin pitch from leads to a deterioration in the thermal performance.