INTRODUCTION: Autologous fat transfer is becoming a more and more widespread procedure in aesthetic breast surgery. Power-assisted technology produces oscillating reciprocal movements of cannula tip, which reproduce the motion of the operator's arm with lower amplitude. The power-assisted mechanism can be applied to the fat liposuction and injection phases. The aim of this study is to report our experience on autologous fat transfer in primary cosmetic breast augmentation using power-assisted liposuction and lipofilling (PALL), our surgical technique and on long-term cosmetic results, and patient-reported outcomes. MATERIALS AND METHODS: A prospective observational study was performed including all patients who underwent PALL cosmetic breast augmentation. Collected data included patient's age, BMI, mean liposuction and fat injection volume, mean operating time, postoperative complications, mean number of grafting procedures required to achieve the desired outcome, cosmetic results and patient satisfaction. RESULTS: A total of 43 patients were included with a mean follow-up of 13.32 months. Mean liposuction and injection volumes were 1884.54 mL and 399.03 mL, respectively. Mean number of grafting procedures was 1.27. With respect to aesthetic outcomes, the mean score for breast volume, shape, symmetry and donor site shape was 4.38, 4.22, 4.27 and 4.42, respectively. Regarding patient satisfaction, the mean score for breast volume, shape, symmetry and donor site shape was 4.22, 5, 5 and 4.77, respectively. CONCLUSION: The current study is the first prospective report on primary cosmetic breast augmentation using PALL. Although our sample of patients is limited, our results showed that PALL primary breast augmentation is an efficient procedure, which leads to satisfactory results for both patients and surgeons. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .