Over the last years, it has become increasingly popular to include both deterministic (i.e., Factor of Safety) and probabilistic (i.e., Probability of Failure) methods in defining acceptability criteria for the design of operating mines and mining projects in Chile. There are many different methods available to calculate Probability of Failure, and each has its advantages and disadvantages. There are methods that are considered more rigorous nevertheless time-consuming to perform, while the less rigorous ones are generally simpler and faster to implement. This paper points out the most frequently used methods for calculating Probability of Failure of rock slopes in Chilean Practice. Among them, there are those that are approximations from Taylor Series, specifically the First Order Second Moment (FOSM), Monte Carlo and Latin Hypercube, Monte Carlo with Response Surface, and Point Estimate Method. In this paper Limit Equilibrium Modeling was chosen to develop a comparative analysis among the reliability methods in a hypothetical slope comprised of Mohr-Coulomb materials and a simplified rock slope from a Chilean mining operation.