AbstractThe quantification of uncertainties in a system and the ability to identify the most influential parameters for a given structural health monitoring (SHM) strategy constitutes an important step for an in‐depth analysis of the problem. It is used in reliability assessment and for the definition of proper inspection intervals. In a recent paper, the authors proposed a methodology for SHM and fatigue life estimations of structures under random loads. This paper expands over those concepts and presents a framework for sensitivity and uncertainty analysis for SHM of structures in the frequency domain. The structure is an Euler–Bernoulli beam, which is modeled with the Ritz method. The conceptual simplicity of the Ritz model keeps the computational cost low. The results showed that the Walker parameter for the crack propagation law, ; the modal damping factor; and the input acceleration are important parameters affecting the variance of the remaining useful life.