Federally qualified healthcare centers (FQHC) treat a large population of low-income patients disproportionately burdened by tobacco use. This study investigated healthcare providers' knowledge, attitudes, and referral patterns of patients who smoke to a state tobacco quitline. The study used a descriptive-qualitative design. In-depth interviews were conducted in 2021 with a sample of healthcare providers recruited from a federally qualified healthcare center (FQHC) in a large city in the Midwest. The interviews were guided by a standardized moderator's guide and lasted 30-45 minutes. Written informed consent was obtained before each interview, and participants completed a brief self-administered survey. Among the 25 participants, 92% were female and 44% were Black. Participants included medical providers (52%), behavioral health providers (16%), and other types of providers (32%). Participants' age and work experience averaged 41.5 and 5.25 years, respectively. Only 32% of providers reported having specialty training in smoking cessation or addiction counseling. Over half (52%) of the participants never or rarely referred patients to the Illinois Tobacco Quitline (ITQL). Providers reported several barriers to referring patients to the ITQL, including limited knowledge about services offered, time constraints, difficulties with the referral process, and lack of feedback between providers and the ITQL. Further, providers described patient-related barriers, including low motivation to quit smoking, language barriers, and failure of patients to respond to calls from the quitline. Recommendations were described for improving patient and provider education, referral processes, and increasing bi-directional communication between providers and the quitline. Providers identified numerous barriers to referring patients for smoking cessation treatment. Addressing the identified barriers requires a multi-faceted approach involving education, streamlined processes, supportive infrastructure, and patient-centered interventions to strengthen provider use and satisfaction with the available resources.