Background: Tobacco smoking increases risk of multiple malignancies, most notably lung cancer, and is a leading cause of premature morbidity and mortality. Tobacco cessation counseling is effective in assisting patients to quit smoking and improving health outcomes, but over one third of smokers report receiving no counseling by healthcare providers. In this study, we investigated rates of tobacco cessation education at ambulatory visits among patients with active malignancy. Methods: We identified ambulatory visits among current smokers with a diagnosis of malignancy using the National Ambulatory Medical Care Survey (NAMCS), a nationally representative sample of ambulatory visits in the US, from 2008 to 2018. We first determined weighted rates of documented smoking cessation counseling. We next evaluated sociodemographic characteristics, provider and visit type, and chronic conditions as determinants of counseling in this population using logistic regression. Results: We identified 2,437 total visits during the study period, representing an estimated 48.9 million such visits in the US. In this cohort, smoking cessation counseling was provided at 14.2% (95% confidence interval [CI] 12.1-16.7%) of visits. Patients were significantly less likely to receive counseling with older age (adjusted OR 0.97 per year of age; 95% CI 0.96-0.98) and less likely in surgical (OR 0.49; 95% CI 0.32-0.75) or medical subspecialties (OR 0.60; 95% CI 0.36-0.99) compared to primary care visits. Sex, race, year of visit, insurance type, and previous visit to the same provider were not significantly related to receipt of counseling. Patients with concomitant COPD were substantially more likely to receive counseling (OR 3.50; 95% CI 2.21-5.53), with 28.4% (95% CI 21.5-36.4%) of such visits including tobacco cessation education. Conclusions: Tobacco smoking is a modifiable risk factor associated with multiple malignancies and substantial non-neoplastic morbidity and mortality. Nonetheless, smokers with current malignancy receive smoking cessation counseling at only about one in seven outpatient visits, with lower frequency with advanced age and at subspecialty visits. As more effective treatments improve survival for cancer patients, further work is needed to improve tobacco cessation efforts that could improve survival and quality of life.