Abstract A major objective of the Patient Protection and Affordable Care Act passed in March 2010 is to ensure access to care for millions of uninsured Americans. This paper expands on existing work that fi nds differential patterns of health care access based on race, ethnicity and nativity by highlighting theoretical links between access to care and assimilation. I examine inequities in health insurance coverage for children across immigrant generations for four major U.S. racial/ethnic groups, testing potential explanations for racial/ethnic-generational differences using data from the 2007 National Survey of Child Health. More time in the country (across generations) does not mean equal increases in insurance for the children of all groups. Whereas the percentage of second generation Hispanic children that are insured doubles from the fi rst to the second generation, the comparative change for Black children is much smaller. Socioeconomic status and other characteristics do not explain away inequities, particularly for Hispanic and black fi rst generation children. Neither the comparative disadvantage of second generation black children nor the advantage of later generation Asian children is accounted for. Language use in the home emerges as a key factor differentiating insurance coverage for second generation Hispanic children. With the growing number of children of immigrants in the United States, this project establishes a crucial baseline on equity of access by which to evaluate implementation of future health care reform.