The aim of this study was to determine the accuracy of the A&D UM-201 device coupled to several cuffs for different arm sizes for office blood pressure (BP) measurement according to the International Protocol of the European Society of Hypertension. Evaluation was carried out in 33 individuals. The mean age of the individuals was 59.3±13.2 years, systolic BP was 145.4±20.6 mmHg (range: 109–186 mmHg), diastolic BP was 87.3±18.0 mmHg (range: 50–124 mmHg), and arm circumference was 30.4±4.2 cm (range: 23–39 cm). The protocol requirements were followed precisely. The UM-201 monitor passed all requirements, fulfilling the standards of the protocol. On average, the device overestimated systolic BP by 3.0±2.1 mmHg and diastolic BP by 2.6±2.0 mmHg. These data show that the A&D UM-201 device coupled to several cuffs for different ranges of arm circumference fulfilled the requirements for validation by the International Protocol and can be recommended for clinical use in the adult population.