The MSP430 family of microcontrollers, as part of its broad portfolio, offers both read-only memory (ROM)-based and flash-based devices. Understanding the MSP430 flash is extremely important for efficient, robust, and reliable system design. Data retention is one of the key aspects to flash reliability. In this application report, data retention for the MSP430 flash is discussed in detail and the effect of temperature is given primary importance. The concepts discussed in this document are applicable to all MSP430 devices that are flash based (F version), in any memory configuration.