Healthcare provider barriers to cessation resources may be undercutting quit rates for smokers with serious mental illness (SMI). The study aim was to examine how providers influence cessation treatment utilization among smokers with SMI. Data were taken from a trial conducted among smokers in Minnesota Health Care Programs. The sample was split into groups of participants with SMI (n = 939) and without SMI (n = 1382). Analyses assessed whether the association between SMI and treatment utilization was mediated by healthcare provider-delivered treatment advice and healthcare provider bias. Results revealed higher rates of treatment utilization among smokers with SMI than those without SMI (45.9% vs 31.7%, p < 0.001); treatment advice and provider bias did not mediate this association. Subsequent individual regression analyses revealed positive associations between treatment advice and treatment utilization (β 0.21-0.25, p < 0.05), independent of SMI status. Strategies to increase low-income smokers' contacts with providers may reduce treatment utilization barriers among these smokers.