ObjectivesWe examined the impact of the Affordable Care Act-mandated elimination of tobacco cessation pharmacotherapy (TCP) copayments on patient use of TCP, overall and by income.MethodsElectronic health record data captured any and combination (eg, nicotine gum plus patch) TCP use among adult smokers newly enrolled in Kaiser Permanente Northern California (KPNC). KPNC eliminated TCP copayments in 2015. We included current smokers newly enrolled in the first 6 months of 2014 (before copayment elimination, N=16,199) or 2015 (after elimination, N=16,469). Multivariable models estimated 1-year changes in rates of any TCP fill, and of combination TCP fill, and tested for differences by income (<50k,50≥75k, ≥75k).Throughtelephonesurveysin2016withasubsetofsmokersnewlyenrolledin2014(n=306),weassessedbarrierstoTCPuse,withresultsstratifiedbyincome.ResultsSmokersenrolledinKPNCin2015versus2014weremorelikelytohaveaTCPfill(9.150k) were less likely to report that clinicians discussed smoking treatments with them (58%) compared with higher income smokers (50≥75k,6775k, 83%), and were less aware that TCP was free (40% vs. 53% and 69%, respectively, P-values<0.05).ConclusionsThe Affordable Care Act's copayment elimination was associated with a modest increase in TCP use and a greater effect among low-income smokers. Uptake may have been enhanced if promoted to patients directly and via providers