OBJECTIVES: Potential predictors of intentional (INA) and unintentional (UNA) non-adherence, and associated health utilities, were examined among women receiving oral treatments for breast cancer (BC). METHODS: US 2010-2015 National Health and Wellness Survey (NHWS) data were analyzed for 679 women who self-reported diagnosis with BC and currently receiving either adjuvant or metastatic oral therapy with selective estrogen receptor modulators or aromatase inhibitors.  Morisky Medication Adherence Scale (MMAS) equivalent items from MMAS-4 and MMAS-8 were summed to create INA (stop taking medicine when feeling better or worse) and UNA (forget or miss taking medication) scores, coded as 1+ vs. 0 non-adherent behaviors.  Binary logistic regressions predicted INA or UNA from treatment group, age, ethnicity, marital status, BMI, employment status, income, health insurance, exercise ≥12 times/month, alcohol consumption ≥2 times/week, smoking, BC stage at diagnosis, Charlson comorbidity index score, and UNA or INA, respectively.  A normal generalized linear model predicted SF-6D health utilities from INA and UNA, controlling for covariates. RESULTS: Among respondents, 6.0% reported INA and 22.4% reported UNA; 3.2% reported both.  Significant (two-tailed p<0.05) predictors of INA included UNA (OR=4.17), age (OR=0.96), income<$25K (OR=5.28), non-overweight BMI (OR=3.90), and non-obesity (OR=4.17).  Significant predictors of UNA included INA (OR=4.13), age (OR=0.97), non-white ethnicity (OR=1.70), obesity (OR=1.77), infrequent exercise (OR=1.60), and smoking (OR=2.14).  INA and UNA were each associated with significantly lower health utilities (b=-0.071 and -0.023, respectively). CONCLUSIONS: Both INA and UNA were associated with poorer health status, with INA having a greater impact.  Younger age was associated with both INA and UNA.  Lower income and non-overweight/obese respondents were at greater risk of INA.  Given relatively high UNA prevalence in BC, targeted interventions may help reduce UNA especially, to improve outcomes among at-risk populations (e.g., younger adults, non-whites, obese or sedentary patients, and smokers).  Findings mirrored previous NHWS research in other diseases.