Time-dependent thermoelectromechanical behavior of metal contacts in microelectromechanical system (MEMS) devices and packaging is studied. The analysis relates the electrical constriction resistance to contact temperature and contact surface evolution over time, using a microcontact asperity creep model for metal microcontacts under continual applied or residual stresses. The effects of contact temperature on constriction resistance are investigated. This work provides guidance toward the rational design of microcontacts with enhanced reliabilities by better defining variables that control the electrical resistance at such microcontcats.