Background: Over 20 states and local jurisdictions in the U.S. have imposed e-cigarette taxes. It is important to evaluate how adult vapers, including those who also smoke respond to e-cigarette taxation. The purpose of this study is to examine factors associated with adult vapers' cost perception of e-cigarettes relative to cigarettes and budget allocations between two products. Methods: We recruited a nationally representative sample of 801 adult e-cigarette users in the U.S., who participated in an online survey in April and May 2023. Nested-ordered logit models and ordinary least squares regressions were used in the analysis. Results: On average, monthly e-cigarette spending was $82.22, and cigarette spending was $118.77 among dual users. Less frequent e-cigarette use and higher state-level e-cigarette taxes were associated with perceiving smoking as cheaper than vaping. Age and exclusive use of tank systems were associated with perceiving vaping as cheaper than smoking. Exclusive use of tank systems was also associated with lower e-cigarette spending. Adults who used e-cigarettes more frequently preferred to report weekly budget on e-cigarettes (p < 0.01), and among dual users, everyday smokers preferred to report weekly (versus monthly) budget on cigarettes compared to someday smokers (p < 0.001). Conclusion: Among US adult vapers, frequencies of tobacco use and e-cigarette device type are closely related to cost measures; and e-cigarette taxes are associated with cost perception of e-cigarettes relative to cigarettes, suggesting potential financial disincentive for vaping. Policymaker may consider imposing differential taxes by e-cigarette product types due to their different costs to consumers.

The authors have declared no competing interest.

This study was funded by the National Cancer Institute (grant# R21CA249757, PI: Ce Shang)

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IRB of The Ohio State University gave ethical approval for this work

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