Unhealthy alcohol use is a serious and costly public health problem. Alcohol screening and brief interventions are effective in reducing unhealthy alcohol consumption. However, rates of receipt and delivery of brief interventions vary significantly across healthcare settings, and relatively little is known about the associated patient and provider factors. This study examines patient and provider factors associated with the receipt of brief interventions for unhealthy alcohol use in an integrated healthcare system, based on documented brief interventions in the electronic health record. Using multilevel logistic regression models, we retrospectively analyzed 287,551 adult primary care patients (and their 2952 providers) who screened positive for unhealthy drinking between 2014 and 2017. We found lower odds of receiving a brief intervention among patients exceeding daily or weekly drinking limits (vs. exceeding both limits), females, older age groups, those with higher medical complexity, and those already diagnosed with alcohol use disorders. Patients with other unhealthy lifestyle activities (e.g., smoking, no/insufficient exercise) were more likely to receive a brief intervention. We also found that female providers and those with longer tenure in the health system were more likely to deliver brief interventions. These findings point to characteristics that can be targeted to improve universal receipt of brief intervention.