We report experimental studies of metastability in the p‐layer of hydrogenated amorphous silicon p‐n junction devices. After reverse bias annealing, we observe a completely reversible metastable increase in the capacitance caused by hole emission from defects in the p‐layer. Hole recapture over an energy barrier during subsequent zero‐bias annealing restores the initial capacitance. The hole emission has a thermal activation energy of 1.3±0.2 eV and the hole capture has an activation energy of 0.89±0.1 eV. We discuss microscopic models of the metastable defect and relate our findings to other carrier‐induced metastability in hydrogenated amorphous silicon.