OBJECTIVES: Clinical evidence shows that adherence levels ≥90% are required to maximize HAART effectiveness on HIV patients. In Mexico, universal access to HAART exists; however, average adherence level is 79.8% (95% CI: 77.8-81.8). The purpose of this study was to analyze two patient-level reminder interventions aimed to increase adherence levels. METHODS: The study design was a cost-effectiveness analysis from the governmental perspective. All the costs were expressed in 2010 constant USD. A natural history of disease dynamic model for HIV was used to estimate the following parameters: CD4 and CD8 cell replication and mortality rates, as well as infectivity rates of individuals simulated. Also, we analyzed data from a national representative survey of HIV patients on HAART (N=2289) and presenting at 50 governmental hospital/clinics to obtain adherence levels. With these parameters we used a Markov model to estimate life expectancy, total patients’ care costs, and therefore cost-effectiveness ratios. Patients were classified as adherent (≥90%) and non-adherent (<90%). We evaluated two patient-level reminder interventions: (1) three reminder text messages (SMS) sent daily to the patient’s cell phone, and (2) a pill reminder. Both were modeled throughout the patients’ lives.  We performed sensitivity analysis for both adherence levels and costs. RESULTS: Of the 2289 patients, 26% were adherent (≥90%) (mean adherence level: 79.8%). We did not find statistically significant differences between adherents and non-adherents in sociodemographic characteristics. Seventy percent reported that HAART daily intake omission is the main reason for non-adherence. Interventions increase life expectancy by 2.6 years (SMS) and 3.1 years (pill reminder) with an incremental cost of $4050 and $5552, respectively. Incremental cost-effectiveness ratios are $207 and $637 per year life gained (3% annual discount rate). CONCLUSIONS: Both interventions are below one GDP per capita; therefore, they are cost-effective and could be considered for implementation in our country.