Introduction: An association between socioeconomic status (SES) and smoke-free private spaces among smokers could be due to heavier smoking among low SES smokers. We assessed whether quantity smoked or SES are independently associated with smoke-free homes or cars in daily smokers. Method: Data were drawn from a cross-sectional telephone survey (2011-2012) of 750 daily smokers age [greater than or equal to]18 years in Quebec, Canada (45% response). Multivariable logistic regression was used to model the independent association between (a) number of cigarettes smoked per day, and (b) each of educational attainment, annual household income, or active employment status and smoke-free homes or cars. Results: Participants were 41.0 years old on average, 57% were female. Median (IQR) number of cigarettes smoked per day was 14 (10, 20). Forty-eight percent of participants reported smoke-free homes; 34% reported smoke-free cars. Quantity smoked was strongly associated with both smoke-free homes and cars. Income and education (but not actively employed) were associated with smoke-free homes. None of the SES indicators were associated with smoke-free cars. Conclusions: Interventions targeting smokers to promote smoke-free homes and cars should incorporate components to help smokers reduce quantity smoked or preferably, to quit. Interventions targeting smoke-free homes will also need to address SES inequalities by education and income. Our data suggest that reduction in quantity smoked may help smokers reduce SHS exposure in cars, but that an inequality lens may not be relevant.