The irreversible isothermal annealing of the as‐deposited defects of hydrogenated amorphous silicon,a‐Si:H, deposited at room temperature by concentric‐electrode radio‐frequency glow discharge is studied using dark and photoconductivity, space‐charge limited current, and time‐of‐flight. The photoconductivity increases as a power law of the annealing time with exponent 0.8. The density of states at the Fermi level, measured by space‐charge limited current, is inversely proportional to the annealing time. These results are compatible with bimolecular annealing kinetics. The dark conductivity obeys a Meyer–Nelder rule during the isothermal anneal.