A swift and efficient load balancing mechanism is required for an effective and optimum resource utilization, less traffic cost, minimized makespan, and improved quality of service (QoS) in a cloud computing environment. However, traditional load balancing techniques are associated with security threats, poor workload distribution, and high latency during resource provisioning. This study proposes an RSA–Fibonacci adaptive technique for secure and efficient load balancing in cloud computing. The proposed strategy incorporates the cryptographic encryption of Rivest – Shamir-Adleman with a recursive Fibonacci-based task allocation mechanism for enhanced security and performance. In this proposed model, RSA encryption is employed to secure workload transmission and resource allocation to determine data integrity and confidentiality across distributed cloud nodes. Simultaneously, task scheduling was optimized using the proportional principle, based on the Fibonacci series, which minimizes traffic cost and improves execution time. The overall results show that the RSA-Fibonacci model enhances system performance and improves security standards better than the existing algorithms, such as the RR, TLB, and ACO-based load balancing algorithms, on the average range of about (35%–40%).