We examined the feasibility of using home blood pressure (BP) telemonitoring devices for managing patients with poor BP control. We enrolled 591 subjects with a diagnosis of hypertension. Patients were randomized to usual care (n = 147) or to the intervention arm (n = 441). Those in the intervention arm were issued with a home BP telemonitoring device. The device transmitted BP readings automatically via the home telephone line. Technical alerts were generated if patients did not transmit their BP readings according to the protocol. During the first six months, 693 technical alerts were generated by 267 patients. About half of these patients (112) generated more than two technical alerts. Resolution of the alerts showed that 61% were caused by patient non-adherence. Patients who generated >2 technical alerts were younger (61 vs. 64 years; P = 0.001) and were more likely to be non-Caucasian (64% vs. 47%, P = 0.002) than those generating 2 or fewer alerts. Despite the potential for improving health care using home BP telemonitoring, certain patients will require more support to use the equipment successfully.