Accelerated temperature and voltage stress tests were conducted on embedded planar capacitors with epoxy–BaTiO3 composite dielectric. The failure modes were found to be a sudden increase in the leakage current across the capacitor dielectric and a gradual decrease in the capacitance. The failure mechanisms associated with these failure modes were investigated by performing data analysis and failure analysis. The time-to-failure as a result of a sudden increase in the leakage current was modeled using the Prokopowicz equation. The values of constants of the Prokopowicz equation, n and Ea , were determined for the epoxy–BaTiO3 composite. The degradation in capacitance was modeled by performing regression analysis. The time-to-failure and degradation models can be used for the qualification tests of embedded planar capacitors, for the development of new composite dielectric materials, and to improve the manufacturing processes of these capacitors.