Hypertension is an important public health concern of high prevalence among adults. It is associated with an increased mortality rate. The prevalence of hypertension in Lebanon has increased during the last decades, affecting around one-third of the Lebanese population. Since diagnosis and treatment of hypertension is associated with a better prognosis, annual screening and raising awareness about this 'silent killer' disease is of extreme value. We conducted a cross-sectional survey in various Lebanese cities in 2019. We recruited adults (≥18 years old) from different sites, through an opportunistic sampling method. For each participant, three blood pressure (BP) readings were recorded and the average of the last two was analysed. In addition, data on lifestyle factors and comorbidities were collected. Participants were considered hypertensive if they had at least one of the following: systolic or diastolic BP ≥140 and/or ≥90 mmHg, respectively, or taking antihypertensive medication. Blood pressure was measured in 7019 participants. The mean age was 46.0 (SD 16.6) years. In total, 2572 participants (36.6%) had hypertension among whom only 64.1% were aware of their disease and 62.3% were on treatment. Blood pressure was controlled in 62.6% of participants taking antihypertensive medications. This study is the largest on hypertension prevalence in Lebanon. The results demonstrated that around one-third of the hypertensive population were not aware of their disease, and that a high percentage was not being treated. These results suggest the need for rapid interventions aimed at raising awareness regarding hypertension in the Lebanese population.