Social markers of acceptance (SMA) are socially constructed criteria (e.g., language skills, shared genealogy, or adherence to social norms) that receiving society nationals use in deciding whether to view an immigrant as a member of the national ingroup. This study had two objectives: 1. to identify the markers considered important by Japanese to accept immigrants in Japanese society, and 2. to examine the type of intergroup conditions that may shape immigrant inclusion by influencing the degree of emphasis placed on SMA: specifically, perceived immigrant threat, contribution, and social status, as well as intergroup boundary permeability and strength of national identification. Native-born Japanese (n = 2000) completed an online survey, where two latent factors emerged representing ethnic and civic markers—suggesting that national identity may have changed in the past 25 years, with Japanese developing a distinct civic conceptualization in addition to a previously existing ethnic one. Multiple hierarchical regressions found significant main effects of perceived immigrant threat, contribution, status, and boundary permeability for both civic and ethnic dimensions, as well as interactions between threat x status and threat x permeability. As hypothesized, threat had positive effects on SMA emphasis, and contribution exerted negative effects—indicating more exclusive and inclusive attitudes among Japanese, respectively. Results for national identity were inconsistent, complementing social identity theory for ethnic markers but contradicting it for civic marker importance. Consistent with social identity theory, immigrants perceived as “low status” triggered endorsement of more restrictive civic and ethnic benchmarks; however, contrary to expectations, increased threat under less porous intergroup boundaries predicted more restrictive civic and ethnic marker utilization. •Identified criteria used in Japanese concepts of national identity.•Showed these criteria change depending upon 5 variables.•Suggests Japanese national identity has changed since 1995.•Integrated threat theory supported & social identity theory had mixed support.•Utilized nationally representative sample (n = 2000) for gender and age.