The primary aim of the study was to assess the association between financial stress, specifically stress about paying rent, mortgage, or utility bills, and smoking tobacco, while accounting for mental health and sociodemographic variables. While there has been much study of the correlation between financial stress and smoking or smoking and mental health, a gap remains in the literature regarding the combined intersectional effect these variables have upon one another. This study utilized data from the 2023 National Health Interview Survey (NHIS). The weighted sample included 76,423,291 participants, and the data analyzed included sociodemographic variables such as age, race, ethnicity, marital status, educational level, financial stress, smoking behavior (every day or some days), and mental health as measured by the PHQ-2 and GAD-2. Findings indicate significant associations between financial stress, mental health, and smoking behavior. Participants experiencing financial stress had 53% higher odds of smoking (OR = 1.53, p < 0.001) compared to those without financial stress. Additionally, anxiety (OR = 1.38, p < 0.01) and depression (OR = 1.23, p < 0.05) were significantly associated with smoking behavior. Race, education level, and marital status also demonstrated intersecting influences on the likelihood of smoking. Non-Hispanic Black participants were more likely to smoke than Non-Hispanic White participants (OR = 1.40, p < 0.05), while higher educational attainment and being married were inversely associated with smoking. Interaction analyses revealed that Non-Hispanic Black participants with depression had lower odds of smoking than Non-Hispanic White participants (OR = 0.46, p < 0.01). These findings highlight the importance of considering intersectional factors, such as race and mental health, when designing smoking cessation programs, as well as addressing mental health alongside smoking cessation.