Background:
Exposure to cigarette smoke is a serious global public health concern that leads to tens of thousands of preventable infant and neonatal deaths globally each year, most of which occur in low- and middle-income countries. Raising tobacco taxes to increase cigarette prices is an effective measure to reduce smoking but is undermined by tobacco companies' differential pricing strategies that maintain budget cigarette prices. Larger price differentials between premium and budget cigarettes are associated with increased infant mortality in the European Union, but this association is not understood globally.

Objectives:
To increase understanding of the association between cigarette price differentials and infant and neonatal mortality globally.

Methods:
Fixed-effect panel regression models were used to assess the association between cigarette price differentials and infant and neonatal mortality globally and by country-level income group using country-level aggregated data on 140 (41 high income and 99 low- and middle-income) countries between 2014 and 2020.

Results:
A 10% cigarette price differential increase was associated with 0.76% increased infant mortality (95% CI: 0.2%-1.3%) and 0.78% increased neonatal mortality (95% CI: 0.2%-1.4%) globally. Decreasing price differentials by 10% was associated with 29,373 averted infant deaths (95% CI: 7,729-50,244), including 18,454 averted neonatal deaths (95% CI: 4,732- 33,122), globally in 2020, 98.4% of which in low-and middle-income countries.

Conclusion:
Higher cigarette price differentials are associated with increased infant and neonatal mortality globally. Associations by income group were not detected.