Abstract Forest plays a crucial role in mitigating soil erosion and preserving organic carbon, especially in mountainous regions of Himalayas. However, limited information exists on soil erosion rate, soil organic carbon stock (SOCS), and associated carbon loss in these areas because of the rugged terrain, which poses challenges for reliable estimation using both traditional and modelling approaches. This study used Fallout Radionuclide-137Cs to assess soil erosion and carbon loss across various forest types. Results showed that mixed forests had the lowest erosion rates, while degraded forests had the highest, following the order of mixed forest