Purpose Although smoking cessation reduces the risk of all-cause mortality, evidence-based cessation treatments are underused. This study examined healthcare provider knowledge of evidence-based cessation treatments and associations between knowledge and clinical practice characteristics. Design Cross-sectional survey. Setting 2020 DocStyles. Subjects 1480 U.S. healthcare providers. Measures Provider knowledge of availability of tobacco use disorder diagnostic criteria, clinical practice guideline availability, treatment efficacy, evidence-based counseling modalities, and medications approved by the U.S. Food and Drug Administration (FDA). Analysis Adjusted odds ratios (aORs), adjusted for personal and clinical practice characteristics. Results Less than half of respondents demonstrated high knowledge of availability of diagnostic criteria (36.8%), cessation treatment efficacy (33.2%), evidence-based counseling modalities (5.6%), and FDA-approved medications (40.1%). Significant differences were found between specialties: compared to internists, family physicians were less likely to have low knowledge of medications (aOR = .69, 95% CI = .53, .90) and obstetricians/gynecologists were more likely to have low knowledge of medications (aOR = 2.62, 95% CI = 1.82, 3.76). Overall, few associations between knowledge and clinical practice characteristics were identified. Conclusion Most providers had low knowledge of the topics of interest, with little variation across clinical practice characteristics, indicating room for improvement. Efforts to improve provider knowledge of evidence-based treatments are an important component of a comprehensive approach to improving delivery and use of cessation interventions and increasing tobacco cessation.