While divorced or living alone, patients with stable cardiovascular disease are at increased risk for adverse cardiovascular events. The importance of marital status following a myocardial infarction (MI) is less clear. We hypothesized that marital status may affect cardiovascular outcomes following MI. We analyzed outcomes among patients with MI who underwent percutaneous coronary intervention from the Canadian Observational Antiplatelet Study (COAPT). Marital status was categorized into 3 groups: married/common-law patients living together; never married; and divorced, separated, or widowed patients. Patients were followed for 15 months and our primary outcome was the occurrence of a major adverse cardiovascular event (MACE), defined as a composite of mortality, repeat acute MI, stroke, or urgent coronary revascularization. Multivariable logistic regression models were performed, with married/common-law patients living together considered the reference group. Among 2100 patients included in analyses, 1519 (72.3%) were married/common-law patients living together, 358 (17.1%) were separated/divorced/widowed, and 223 (10.6%) patients were never married. Dual antiplatelet therapy use after 15 months was similar across groups (75.4%, 77.8%, and 73.6%, respectively). The risk of MACE after 15 months was similar among married patients living together (12.7%; referent) compared with patients who were never married (13.9%; adjusted odds ratio: 1.09, 95% confidence interval: 0.58-2.07, P = 0.79) and patients separated/divorced/widowed (14.3%; adjusted odds ratio: 0.71, 95% confidence interval: 0.40-1.25, P = 0.23). Similarly, the risk of individual endpoints, including mortality, was similar across the 3 groups. Among patients stabilized following an MI, we found no association between marital status and 15-month outcomes.