Preventing, diagnosing, and controlling high blood pressure is a global health priority. The self-measurement of blood pressure is therefore fundamental and should be done with devices validated by recognized protocols, although most are not. The most widely used and current protocols are the 2010 European Society of Hypertension (ESH) revision and the 2018 Association for the Advancement of Medical Instrumentation (AAMI)/ ESH/ the International Organization for Standardization (ISO) universal standard, respectively. The aim of this study was to find out which blood pressure measuring devices have been adequately validated by the above protocols. A narrative review of blood pressure device validations was conducted by searching the PubMed database. From 52 records identified, 37 studies were included. Most validations follow the 2010 revision and only six follow the 2018 protocol, which is more demanding. Almost all validated sphygmomanometers are automated oscillometric sphygmomanometers in the general population. Wrist devices and devices combining new technologies are also validated, as well as in specific populations, such as the obese, pregnant women, or children. There is sufficient evidence to confirm that the universal AAMI/ ESH/ISO standard is considered the protocol of the century. However, it is necessary to increase the number of validations following it and, above all, validations of the new technologies that are invading the current market.