BACKGROUND This study provides binge drinking population estimates for California adults by gender and detailed race/ethnicity categories. This information may be helpful for planning targeted initiatives to decrease binge drinking. METHODS Data were from the 2007 and 2009 California Health Interview Surveys. The 98 662 respondents represent an annual estimated population of 27.2 million adults. Survey adjusted binary logistic regression was used to calculate gender-specific binge drinking population rates and multinomial logit regression to estimate binge drinking frequency. RESULTS Adjusting for socio-demographics, any binge drinking during the past year was reported by 31.0% (95% Confidence Interval = 30.5-31.4%) of men and 18.0% (17.7-18.3%) of women. Rates among White men and women were 30.5% and 19.6%, respectively. Binge drinking rates ranged from 11.9% among Chinese to 42.9% among Mexican men and from 4.8% among Vietnamese to 25.7% among "Other Latino" women. Five race/ethnicity categories of men and seven categories of women were significantly less likely to binge drink compared to Whites. Although Whites had the highest overall binge drinking rates, an estimated 12.5% of White men binge drank less than monthly, significantly exceeded by Mexican and Central American men, 19.9 and 19.6%, respectively. An estimated 9.6% of White women binge drank less than monthly, exceeded only by "Other Latino" women, 13.6%. CONCLUSIONS These findings underscore the importance of detailed gender and race/ethnicity breakdowns when examining any binge drinking. Furthermore, there is variability across Asian and Latino subgroups in the frequency of binge drinking episodes, which is not evident in broad-group population studies.