Inclusion Criteria:  diagnosis of non-cancer chronic (>3 months) back pain (confirmed in medical record or by current provider); Pain duration of >=3 months with an average intensity of >/= 4/10 as assessed by Graded Chronic Pain Scale (GCPS); smoking at least 10 cigarettes per day for > 2 years; expired breath CO concentration > 10 ppm; have an iPhone or Android smartphone capable of running EMA software  Exclusion Criteria:  actively taking steps to quit smoking; inability to attend all required experimental sessions; report of significant health problems; systolic blood pressure > 160 or diastolic blood pressure > 100; resting heart rate > 100; breath alcohol level > 0.0; current use of opioid pain relievers; lifetime history of bipolar or psychotic disorder; current unstable psychiatric disorder as assessed by the MINI; use of non-cigarette tobacco products > 8 times in the past 30 days; current use of nicotine replacement therapy (NRT) or other smoking cessation strategy; use of Spectrum investigational cigarettes in the past year; quit attempt in the past 30 days resulting in > 3 days abstinence; past year alcohol or substance use disorder; use of illegal drugs as measured by urine drug screen; pain complaint due to specific medical conditions (e.g., cancer, rheumatoid arthritis), migraine, fibromyalgia, or complex regional pain syndrome; spine surgery within the past 2 years or planned surgery within the timeframe of the study; current disability litigation pending; positive pregnancy test among women