Threshold switching has been observed and studied in thin films of NbOx(x?2) in the sandwich configuration and in a single‐crystal device having both a gap and sandwich configuration. The recovery curve has been determined by measuring the reswitching voltage after a specific zero‐voltage interruption time. Data indicate a maximum allowable interruption time of about 200 ns without a switch‐off transition. This is interpreted as the distribution trapped‐carrier lifetime for polycrystalline NbO2.