Despite the well-recognized importance of prevention and early treatment of hypertension, the majority of adults in Nepal are not aware of their high blood pressure (BP) and are left untreated. In this paper, we report the result of the May Measure Month 2021 campaign in Nepal: a nationwide community-based hypertension screening campaign. An opportunistic cross-sectional survey was conducted in 15 districts between September 2021 and December 2021. An individual was included if aged 18 years or more and provided informed consent. Structured questionnaires were administered, and BP was measured three times in a sitting position by trained volunteers. A total of 5172 participants were included. The median age (interquartile range) was 37 (25-51), and 49.9% were female. The mean (SD) of the systolic and diastolic BP was 123.9 (14.9) and 80.2 (9.3) mmHg, respectively. A total of 1066 participants (20.6%) were identified as hypertensive (systolic BP ≥ 140 mmHg or diastolic BP ≥ 90 mmHg or on antihypertensive medication), of whom 399 (39.5%) and 298 (29.5%) were aware of their BP status and treated with at least one antihypertensive medicine, respectively. Blood pressure control (<140/90 mmHg) was achieved in 15.6% of all hypertensives and in 56.0% of treated individuals. Multivariate logistic regression showed an association between hypertension and the following variables: every 1-year increase of age [odds ratio (OR) = 1.13 (1.11-1.15) if age < 40 and OR = 1.05 (1.04-1.06) if age ≥ 40], male [OR = 1.57 (1.33-1.89)], regular alcohol use [OR = 1.59 (1.30-1.93)], and diabetes [OR = 2.63 (1.93-3.58)]. Hypertension awareness, treatment, and control were suboptimal in Nepal. This study supports a strong need to scale up community-based hypertension programmes in Nepal and raises the possibility of task sharing with community health workers.