Background: Non-marital fertility differs considerably by race, ethnicity, and nativity. These differences arise largely from racial and ethnic disparities in contraceptive practices. Empirical work has not assessed the relative importance of the various mechanisms proposed to account for racial, ethnic, and nativity differences in contraceptive behavior among never married women. Objective: Our objective is to describe racial, ethnic, and nativity disparities in contraceptive practices and determine the relative importance of the various mechanisms proposed to explain those disparities among never married, non-cohabiting women. Methods: Pooling data from the 2006‒2010 and 2011‒2013 National Survey of Family Growth (NSFG), we compare the age- and parity-standardized patterns of contraceptive use among never married, non-cohabiting Mexican immigrants, US-born Mexican Americans, Blacks, and Whites. We also examine the extent to which socioeconomic characteristics, access to family planning, and attitudes towards family life give rise to group differences in patterns of contraceptive use. Results: Never married, non-cohabiting Whites are more likely than their minority counterparts to use very effective methods of contraception. Socioeconomic disparities explain some of the group differences in contraceptive practice. Differing levels of access to family planning also explain a significant portion of the difference in contraceptive practice between Whites and Mexican immigrants. Conclusions: Policies aimed at alleviating socioeconomic inequality and differential access to family planning services may be effective at reducing disparities in contraceptive use between White and non-White never married, non-cohabiting women, especially White/Mexican-immigrant differences.