Elevated blood pressure (BP) is a growing burden worldwide and is the leading cause of mortality and disability-adjusted life years all over the world. May Measurement Month (MMM) is a global initiative aimed to increase awareness of high BP initiated by the International Society of Hypertension, to identify individuals in need of improved hypertension care, and to improve BP screening worldwide. An opportunistic cross-sectional survey of volunteers aged ≥18 years was carried out in accordance with standard MMM protocol in 2021. The study was conducted in public areas, both indoor and outdoor, as well as in primary and secondary healthcare centres. A total of 5777 individuals (mean age 51.8 ± 16.1 years, 49.8% female) were screened. After imputation, 45.7% participants had hypertension and 43.7% of them were aware of their high BP. Of 2640 participants with hypertension, 887 (33.6%) were on antihypertensive treatment, of whom 32.4% were on single medication, 29.7% on two medications, and 37.9% on three or more. Only 42.2% of those on medication had controlled BP (<140/90 mmHg), whereas of the participants with hypertension overall, 14.2% had controlled BP. We found that the prevalence of inadequately treated hypertension remains high in Armenia and may represent a vital contributor to the growing burden of non-communicable diseases.