Introduction: The prevalence of light and intermittent smoking (LITS) is increasing as the prevalence of heavier smoking continues to fall. The purpose of this study was to examine changes in LITS over time among Blacks, Hispanic/Latinos (Latinos) and non-Hispanic Whites (Whites). Methods: Data from the California Tobacco Surveys from 1990, 1992, and 1996 (Time 1 [T1]) were combined and compared to combined data from 1999, 2002, 2005, and 2008 (Time 2 [T2]). T1 participants (N = 50,424) included Blacks (n = 3,029), Latinos (n = 7,910), and Whites (n = 39,485). T2 participants (N = 53,005) included Blacks (n = 5,460), Latinos (n = 14,273), and Whites (n = 33,246). Results: LITS increased by a factor of 12.9% to a rate of 79.6% (76.0-83.2) among Latinos, by 19.4% to a rate of 74.4% (70.9-77.9) among Blacks, and by 51.7% to a rate of 48.9% (47.5-50.3) among Whites. In unadjusted analyses at T1, females were more likely to be LITS than males across ethnic groups. At T2, this sex difference was maintained among Whites, but not Blacks and Latinos. Females were significantly more likely to be LITS than males when controlling for demographic variables. Conclusions: The present study found that LITS rates increased over time for male and female Black, Latino and White adults. There is a need for increased tobacco control attention to LITS across all ethnic groups, but with additional focus on Blacks, Latinos, and women who have the highest rates of LITS.