Tube-in-tube heat exchangers are extensively used in various industrial applications due to their compact design and ease of maintenance. However, the growing need to augment their thermal performance leads to the implementation of different fins on the tube surface. This study aims to numerically investigate the potential utilization of helical fins to enhance the thermal performance and capacity of the heat exchangers. The effect of varying fin pitch and helix angle is systematically analyzed for two different fin shapes, i.e., triangle and rectangle. The fin height and operating parameters are kept same for all the designs. The results highlighted a noteworthy improvement in the thermal conductance with the incorporation of fins on the tube surface. The use of helical fins provided an additional augmentation in compared to straight fins as the thermal conductance increases alongside the increase in helix angle. Specifically, the triangle fin geometry demonstrates a peak improvement of 548%, whereas the rectangle fin design exhibits an even more notable boost of 560% in the thermal conductance with a helix angle of 10°. Moreover, the study reveals that an increase in fin pitch results in a decline in thermal performance.