An electronic vapor provision device comprises a body and a vaporizer. The body comprises a power cell and a processor, and the vaporizer is releasably connectable to the body. The processor is configured to enter a sleep mode when the vaporizer is connected to the body and the device is inactive for an inactive time. Furthermore, the processor is configured to leave the sleep mode and enter a usable mode when the vaporizer is disconnected from the body then reconnected to the body.