The objective of this study was to review software errors known as single event upsets (SEUs) or bit flips due to cosmic rays in epilepsy neurostimulators.A case report of a single event upset or bit flip is discussed; device manufacturers and publicly available data were queried for both incidence and types of error as well as strategies of software error mitigation.Neurostimulators, like other implanted devices such as pacemakers, are prone to single event upsets. Strategies for SEU mitigation are reviewed.Cosmic radiation can threaten RAM and settings of neurostimulators; neuromodulation teams and device designers need to take this threat into account when designing multifunctional neuromodulation systems.