Objectives: This study examines how the linkage of surveys to death records differs for Hispanics and non-Hispanic Whites and how such differences affect estimates of ethnic differences in U.S. adult mortality. Method: I use data from the 1989-2000 National Health Interview Survey (NHIS) linked to the National Death Index (NDI) through 2002. Analyses assess how match score and match class vary by ethnicity, nativity, and age and whether mortality hazard ratios are sensitive to shifts in match criteria. Results: Linkage quality is lower for Hispanic and foreign-born adults than for non-Hispanic White and U.S.-born adults. Modification of the linkage criteria determine whether the Hispanic mortality advantage is observed among middle-aged adults. Discussion: The accuracy of adult mortality estimates depends on the quality of the linkage between surveys and death records.