This study investigates the moment–rotation behavior of eaves connections in cold-formed steel portal frames, with a focus on enhancing moment resistance and load-bearing performance through the effective design of bolted connections. Finite Element Analysis (FEA) was conducted using shell elements in the ANSYS software environment to model the structural response of the frames and their connections under loading conditions. The eaves connection setup studied comprises two individual C-sections, an eaves bracket, and associated lateral supports. The study encompasses a comprehensive numerical analysis of various bolt group configurations and the positional influence of the knee plate, along with comparative evaluations of bolted versus welded connections. Particular attention is given to the impact of moment of inertia across different cross-sectional profiles. Results indicate that the absence of a knee plate significantly increases stress concentration and decreases moment capacity, while its presence in the original position yields optimal structural performance. It was further observed that the moment of inertia is a governing parameter influencing the ultimate moment capacity, with sections exhibiting higher inertia demonstrating superior resistance to bending and reduced rotational deformation. Failure analysis revealed that bolts located near the edge of the eaves plate are prone to shearing, and that the dominant failure modes include bending of the eaves bracket and shear failure of bolts. These mechanisms lead to upward displacement of the bracket and relative rotation between the C-section members, inducing bending moments at the connection. From a sustainability perspective, the research supports the efficient use of materials and the optimization of joint configurations to extend the service life of cold-formed steel structures, thereby minimizing waste and resource consumption. The deconstruction principle is inherently supported by the bolted connection strategy, allowing for disassembly, reuse, and recycling of structural elements making this study highly relevant in the context of sustainable construction practices and the circular economy.