Although early diagnosis has been recognized as a key strategy to improve outcomes of Alzheimer’s disease and related dementias (ADRD), the effect of receiving a diagnosis on patients’ well-being is not well understood. This study addresses this gap by examining if receiving a dementia diagnosis influences social relationships. Data from the 3 waves (2012, 2014, and 2016) of the Health and Retirement Study were utilized as part of this study. This study examined whether receiving a new diagnosis of ADRD changed subsequent social relationships (social networks, social engagement, and social support). Regression analyses with inverse probability weighting were performed to estimate the impact of receiving a dementia diagnosis on changes in social relationships. Receiving a new diagnosis of ADRD reduced both informal and formal social engagement. We found no statistically significant impacts of receiving a diagnosis of ADRD on social networks and social support. Results suggest that receiving a new diagnosis of ADRD may have unintended impacts on social relationships. Practitioners and policymakers should be aware of these consequences and should identify strategies to alleviate the negative impact of receiving a diagnosis of ADRD and methods to mobilize support networks after receiving a diagnosis.