OBJECTIVES: Medication non-adherence and treatment satisfaction are significant barriers to achieving treatment outcomes and associated with increased healthcare costs among patients with hypertension. Using a novel patient registry, we assessed factors associated with satisfaction and non-adherence to hypertension medications.  METHODS: We analyzed data from MediGuard.org, a free medication monitoring service covering over 2.6 million members in the US, UK, France, Germany, Spain, and Australia.  As part of site operations, the service sends a quarterly member survey to solicit feedback on their medications using the Treatment Satisfaction Questionnaire for Medication (TSQM) and Medication Adherence Report Scale (MARS-5), valid and reliable instruments, amongst other questions. The TSQM yields scores on effectiveness, side-effects, convenience, and global satisfaction domains. Non-adherence was defined as a score of ≤24 and adherence as a score of 25 on MARS-5. Multivariate logistic regression and multivariable linear regression were performed to identify patient characteristics (age, gender, number of medications, severity, and hypertension drug class) and self-reported reasons associated with non-adherence and treatment satisfaction. RESULTS: Between November 2011 and June 2012, 556 MediGuard.org members completed a survey related to an ACE or ARB: ACE=358 (64.4%), ARB=198 (35.6%). Patients had mean age of 62.4 (SD:10.5) years (ACE=61.7 years, ARB=63.6 years) and 56.3% were female (ACE=58.1%, ARB=53.1%). Overall, 51.5% reported medication non-adherence. The mean TSQM score on effectiveness was 70.4(19.3), side-effects was 95.6(13.8), convenience was 84.6(14.0), and global satisfaction was 67.4(19.2). Forgetting, don’t like to take pills/give injection, and gender were significantly associated with non-adherence (p<0.05). Age, gender, and don’t like to take pills/give injection were significantly associated with effectiveness, side-effects, and convenience domain (p<0.05), respectively. Age and don’t like to take pills/give injection were significantly associated with global satisfaction (p<0.05). CONCLUSIONS: In addition to patient characteristics, patient preferences are important to potentially improve adherence and satisfaction to hypertension medications.