In this paper, deterministic and probabilistic approaches of failure modeling of high‐density polyethylene (HDPE) pipes have been introduced. They are based on determining the experimental parameters of HDPE through burst and tensile tests. In fact, reliability criteria have been determined through 11 damages models, and the critical life fraction have been reached for both of the approaches. Besides, the mean time between failures (MTBF), the probability density, and the failure rate have been defined for each loading level by using the Weibull parameters. The comparison of the failure rate bathtub curves to those obtained through the damage‐reliability curves present a fast tool to choose accurately the maintenance decision to undertake the sudden failures' occurrence and oblige the preventive measures instead of the corrective ones. The reliability prediction through a simplified equation of MTBF have been developed. The introduced approaches can be applied to all the thermoplastic pipes.