Embodiments of switching between multiple operating systems (OSes) using sleep state management and sequestered re-baseable memory are generally described herein. Embodiments of the invention allow one OS to be suspended into S3 or sleep mode, saving its state to memory and turning off its devices. Then, another sleeping OS can be resumed from another location in memory by switching a memory base addressed to a sequestered memory region and restoring its device state. Other embodiments may be described and claimed.