This paper presents a method for assessing the reliability of a corroded pipeline placed in series, with special consideration given to the effect of the length scale imposed by each segment of the pipe. The features of corrosion in different pipe segments are statistically correlated; thus, a failure in one section may impact the adjacent sections. Herein, using a correlation distance parameter, such statistical correlation is described considering the length-scale effects. The reliability of the corroded pipeline is presented in the form of a failure probability. The results show that analysing a corroded pipeline by considering length-scale effects produces a higher failure probability compared with the case where such effects are excluded, even when the parameters that govern corrosion in a pipeline are included in the analysis. © Universiti Malaysia Pahang, Malaysia.