In this paper the reliability of AC contactor is studied. In the present scenario where the dependency on electrical energy has increased immensely, there is a huge pressure on power system network for its reliable operation. Under this condition failure of any component in electrical network can cause huge loss of economy and continuity of supply. This Paper is focused towards estimating the remaining useful life of the contactors through its characteristics parameter i.e. Contact resistance and Contact Compression. Sampies of rating 9A, 440V, 230V (coil voltage) underwent Electrical Endurance Test and during the testing, behavior of these two characteristic parameters is studied in accordance to find the relation between Contactors life, contact resistance and contact compression. The results obtained helped in predicting the health or remaining life of contactor. Hence, based on experimental data reliability of the system is estimated using Reliasoft Software.