Background/Objectives: Mastectomy is a surgical option for breast cancer when conservative treatment is unsuitable, and it is also performed prophylactically in high-risk women. Various surgical techniques can be used for mastectomy, including electrosurgery, which can cause thermal damage to tissues, reducing surgical precision and delaying wound healing. This study aims to compare electrical plasma surgery and hydrodissection, which appear to be the least traumatic methods, to determine the better option for performing mastectomy with immediate reconstruction. Methods: Conducted at the “Breast Unit” of AO “OrdineMauriziano Umberto I”, this study analyzed 56 patients undergoing 65 mastectomies (9 bilateral, 47 unilateral). A total of 16 were prophylactic, and 49 were oncologic. All patients received immediate subpectoral reconstruction. Data collected included preoperative medical history, pain, drain flow, blood transfusions, hemoglobin levels, and hospital stay duration. Complications were graded using the Clavien-Dindo classification. Results: Both groups were similar in age, body mass index (BMI), smoking habits, and comorbidities. Patients who underwent hydrodissection reported more pain on the first and second postoperative day and had longer hospital stays. The drop in hemoglobin from pre- to postoperative and the volume of surgical drains on the day of surgery and the first and second postoperative days were comparable between groups. Early complications and reintervention rates (Clavien-Dindo grade 3) were similar between techniques. Conclusions: Electrical plasma surgery offers better early postoperative outcomes in terms of pain and hospital stay, although overall complication and reintervention rates are unaffected by the technique used. Larger randomized studies are needed to confirm these findings and optimize patient management.