Race strongly patterns hostility toward immigrants in the US, but few studies have detailed when racial and national identity boundaries act in concert to promote prejudice toward immigrants. The current work positions “American-ness” (i.e. what is means to be an American) as a potentially racialized concept that may elicit racial in-group boundaries when assessing immigrants. I reference literature on symbolic boundary making to offer a contingent form of national identity, American Appropriation, to test this premise. Using the 2004& 2014 General Social Survey (n=1760), I test the association between race, American Appropriation, and immigrant hostility. Regardless of race, those who grant importance to American Appropriation are likely express hostility towards immigrants. White/Black and Latino/non-Latino racial boundaries appear when assessing attitudes about immigrants, dependent upon the particular measure of immigration perspectives and dimension of American Appropriation. I find that American Appropriation strengthens racial boundaries in the formation of immigration hostility.