Venkataramani A, et al. - A cross-sectional, county-level study was carried out to investigate whether social mobility is associated with income-related differences in life expectancy in the United States. This research utilized data from 1,559 counties in the United States to evaluate the relationship of social mobility with average life expectancy at age 40 years by gender and income quartile among adult men and women over the period of January 2000 through December 2014. This study applied bayesian generalized linear multilevel regression models to determine the relationship, with adjustment for a range of socioeconomic, demographic, and healthcare system characteristics. The evidence displayed that higher county-level social mobility was correlated with smaller county-level gaps in life expectancy by income in this cross-sectional study.