Reliability specifications for solder joints, as well as for all electronic components, become a fundamental element in the qualification of an electronic product. This importance increases if new lead-free alloys are considered and then under test. An accelerated thermal test is proposed for an early reliability evaluation and the definition of failure parameters is addressed. The traditional technique employed for failure monitoring of solder joints is the DC resistance measurement. This paper reviews and assesses the DC resistance monitoring during reliability tests of lead-free solder materials used for electronic boards production. Moreover through a failure prognosis measurement technique, considering wideband measurements, the possibility to identify the failure occurrence earlier than the DC resistance method is evaluated. An experimental study on a pass band filter soldered by a new lead free alloy is performed to evaluate reliability performance.