PurposeAsian American, Native Hawaiian, and Pacific Islander (AANHPI) patient populations are often defined as one monolithic group in medical research despite cultural, socioeconomic, and clinical heterogeneity. Although the general AANHPI population is underrepresented in reception of postmastectomy breast reconstruction, existing literature has not characterized the disaggregation of such rates for AANHPI ethnic subgroups. MethodsPatients who underwent mastectomy were identified in the 2007 to 2020 registries within the Surveillance, Epidemiology and End Results database. Patients were stratified by race and ethnicity, and additional demographic and oncologic variables were collected. Multivariate binary logistic regression was conducted to assess for reception of postmastectomy immediate breast reconstruction (p < 0.05). ResultsAmong 33,422 AANHPI patients who underwent mastectomy, South Asian patients were associated with the highest breast reconstruction rates (33%) and Melanesians with the lowest (15%). Overall, AANHPI patients were associated with a lower breast reconstruction rate than non-Hispanic Whites (27% vs. 35%; p < 0.001). This difference increased from 6.4% in 2007 to 10% in 2020. After controlling for demographic and oncologic covariates, all AANHPI ethnic subgroups predicted a lower likelihood of breast reconstruction than non-Hispanic Whites (p < 0.001). Odds ratios for reconstruction ranged from 0.17 [95% confidence interval (95% CI), 0.11–0.27] for Melanesian patients to 0.45 (95% CI, 0.42–0.48) for South Asian patients. ConclusionsDisparities in the receipt of immediate breast reconstruction exist within the AANHPI patient population in the United States. This analysis supported the need for disaggregation in plastic surgery research for improved knowledge and targeted interventions.