BACKGROUND: Patient portals are secure online platforms that have shown potential to facilitate shared decision-making (SDM) in cardiovascular disease risk reduction. However, the role of health care providers (HCPs) in offering patient portals within the context of SDM remains poorly understood. This study aimed to examine the relationship between patient portal access offered by HCPs and patient engagement in SDM among adults with or at risk of cardiovascular disease in the United States (US). METHODS: This population-based cross-sectional study included a nationally representative sample of US adults from the 2022 Health Information National Trends Survey. We performed weighted multivariable logistic regression analyses to examine the association between patient portal access offered by HCPs and patient engagement in SDM. RESULTS: The study included a representative sample of 4234 adults with or at risk of cardiovascular disease. The mean age of the participants was 48.5 years (SD, 17.1), with 50.6% female and 62.8% White. Adults who were offered access to patient portals by HCPs (adjusted odds ratio, 2.11 [95% CI, 1.34-3.32]) and encouraged to use them (adjusted odds ratio, 1.68 [95% CI, 1.15-2.45]) were more likely to engage in SDM than their counterparts, adjusting for covariates. The extent of this association varied by demographics and social determinants of health. CONCLUSIONS: Offering access to patient portals and encouragement to use them by HCPs was associated with high SDM among US adults with or at risk of cardiovascular disease. Future research is needed to explore the possible causal relationship between patient portal use and access and patient engagement in SDM.