Unlike a typical electromechanical relay, there are several variables that will directly impact the life expectancy of a solid state relay in a given application. These variables primarily revolve around the electrical characteristics of the application, but some mechanical issues also impact the relay's life expectancy.

To assist with evaluating the reliability of their Solid State Relays, Crydom commissioned an independent specialized company to analyze the designs of several different Crydom SSR models. The final result yielded a MTBF rating of between 5 million and 34 million hours, depending upon the product family.