This paper investigates the feasibility of using an in situ wet layup fiber-reinforced polymer (FRP) repairing system to extend the service life of electric distribution and transmission wooden poles. The effectiveness of the FRP strengthening method was evaluated through field tests performed on Class-4 deteriorated wooden poles and a step-by-step rapid installation procedure was developed. Results indicated that the application of the in situ wet layup FRP system increased the load capacity of the poles where more than 85% of their original capacity was restored. In addition, the repaired poles exceeded the minimum lateral load required by the NESC and ANSI 05.1 codes indicating that it would be more cost-effective repairing the poles than replacing them. Moreover, in addition to the cost savings, the FRP system extended the service life of the deteriorated poles up to 30 years.