This study aims to investigate the patient-reported outcomes (PROs) and complications of distinct implant-based breast reconstruction modality for patients with postmastectomy radiation therapy (PMRT). A retrospective review was conducted on breast cancer patients with stage II-III disease who performed implant-based breast reconstruction following with PMRT between September 2016 and April 2022. The patients were categorized into two matched groups: (1) patients receiving prepectoral breast reconstruction (PBR) or (2) subpectoral breast reconstruction (SBR) followed by PMRT. Following reconstruction, the patients were further compared for PMRT with the tissue expander (PMRT-TE) versus PMRT with permanent implant (PMRT-PI). PROs were measured with BREAST-Q questionnaire. Early and late complications were recorded and analyzed. A total of 55 eligible patients were recruited. Patients who underwent PBR reported significantly higher satisfaction with breasts scores (P = 0.003) compared with the SBR group. The PMRT-TE group had higher satisfaction with breasts (P = 0.001) but lower physical well-being (P = 0.029) scores compared with PMRT-PI group. Moreover, patients in SBR cohort had a higher risk of capsular contracture (Baker grade III or IV) (20.5% vs 6.3%) and implant dislocation (48.7% vs 12.5%) than patients in PBR cohort. Patients in PMRT-PI group had a slightly higher rate of capsular contracture (Baker grade III or IV) than PMRT-TE group (20.8% vs 12.9%). PBR was associated with lower rates of late complications, especially for implant dislocation, and higher satisfaction with breasts scores compared to SBR. In addition, compared to PMRT-TE with PMRT-PI, patients in PMRT-TE cohort reported superior PROs of satisfaction with breasts.