California's landmark 1994 Smokefree Workplace Act contained numerous exemptions, or loopholes, believed to contribute to inequities in smokefree air protections among low-income communities and communities of color (e.g., permitting smoking in warehouses, hotel common areas). Cities/counties were not prevented from adopting stronger laws. This study coded municipal laws and state law changes (in 2015-2016) for loophole closures and determined their effects in reducing inequities in smokefree workplace protections.Public health attorneys reviewed current laws for 536 of California's 539 cities and counties from January 2017 to May 2018 and coded for 19 loophole closures identified from legislative actions (inter-rater reliability, 87%). The local policy data were linked with population demographics from intercensal estimates (2012-2016) and adult smoking prevalence (2014). The analyses were cross-sectional and conducted in February-June 2019.Between 1994 and 2018, jurisdictions closed 6.09 loopholes on average (SD=5.28). Urban jurisdictions closed more loopholes than rural jurisdictions (mean=6.40 vs 3.94, p<0.001), and loophole closure scores correlated positively with population size, median household income, and percentage white, non-Hispanic residents (p<0.001 for all). Population demographics and the loophole closure score explained 43% of the variance in jurisdictions' adult smoking prevalence. State law changes in 2015-2016 increased loophole closure scores and decreased jurisdiction variation (mean=9.74, SD=3.56); closed more loopholes in rural versus urban jurisdictions (mean=4.44 vs 3.72, p=0.002); and in less populated, less affluent jurisdictions, with greater racial/ethnic diversity, and higher smoking prevalence (p<0.001 for all).Although jurisdictions made important progress in closing loopholes in smokefree air law, state law changes achieved greater reductions in inequities in policy coverage.