Implant-based reconstruction remains the most common form of postmastectomy breast reconstruction. With ever-evolving device characteristics, including the advent of high-profile, cohesive, fifth-generation implants, the incidence of anterior-posterior flipping of implants is presenting a new challenge. Patient and device characteristics associated with this phenomenon have yet to be fully elucidated. Patients who underwent nipple- or skin-sparing mastectomy with subsequent 2-stage or direct-to-implant reconstruction with smooth implants between 2015 and 2021 were retrospectively identified and stratified by incidence of implant flipping. Patient, procedural, and device characteristics were evaluated. Within 165 patients (255 reconstructed breasts), 14 cases of implant flipping were identified (flip rate 5.5%). All flips occurred in patients with cohesive implants (odds ratio [OR], 87.0; P = 0.002). On univariate analysis, extra full implant profile (OR, 11.2; P < 0.001) and use of a smooth tissue expander for 2-stage reconstruction (OR, 4.1; P = 0.03) were associated with flipping. Implants that flipped were larger than those that did not (652.5 ± 117.8 vs 540.1 ± 171.0 mL, P = 0.0004). Prepectoral implant placement (OR, 2.7; P = 0.08) and direct-to-implant method (OR, 3.17; P = 0.07) trended toward association, but this effect was not significant. Patient BMI, weight fluctuation during the reconstructive course, mastectomy weight, AlloDerm use, and history of seroma or periprosthetic infection were not associated with flipping. Patients who receive a highly cohesive, high profile, larger implant are at increased risk for implant flipping. In addition, patients who receive a smooth tissue expander are more likely to experience flipping of their subsequent implant, compared with those who had textured tissue expanders. These characteristics warrant consideration during device selection to minimize discomfort, aesthetic deformity, and the need for reoperation.