OBJECTIVES We estimated the relationship between nursing home admission and non-adherence to anti-hypertensive medications. We calculated the incremental proportion of nursing home admission that was due to non-adherence, and the annual incremental cost of the proportion of nursing home admission due to non-adherence. METHODS We calculated adherence scores in a cohort of 225,624 subjects with hypertension from the MarketScan® database. We used a generalized linear model with a binomial distribution and a log link to estimate adjusted relative risks of nursing home admission. We calculated the fraction of nursing home admission attributable to non-adherence. RESULTS We showed that non-adherence to anti-hypertensive medications increases the risk of nursing home admission. Among non-adherent subjects, 10.8% were admitted to nursing homes. In the general population of community-dwelling elderly subjects, 1.9% of nursing home admissions were attributable to non-adherence to anti-hypertensive medication. Extending these results to the United States elderly (age ≥ 65) population with hypertension, we found that annually 28,372 subjects were admitted to nursing homes in 2002 because of non-adherence to anti-hypertensive medications. In 2002, the cost of nursing home admission due to non-adherence was estimated to be $1.7 billion. CONCLUSIONS Anti-hypertensive medication non-adherence was a risk factor for elderly transitioning to long-term care facilities. Since non-adherence may be viewed as a proxy for lack of social support, our results show the potential benefits related to interventions that could provide social support to elderly patients, such as assistance with medication administration.