Although breast reconstruction is an integral part of breast cancer treatment, there is little high-quality evidence to indicate which method is the most effective. The objective of this study is to compare implant-based and autologous breast reconstruction, in non-radiated patients. The primary outcome is patient reported breast-specific quality of life/satisfaction and the secondary outcomes are complications, factors affecting satisfaction, and cost-effectiveness. Moreover, the study aims to improve the evidence for trial decision-making in breast reconstruction. Randomized controlled trials (RCT) are generally thought to provide the most solid scientific evidence, but there are significant barriers to conducting RCTs in breast reconstruction, making both recruitment and achieving unbiased and generalisable results a challenge. The study design partially randomised patient preference trial (RPPT) might be a way to overcome these challenges. In the present study, patients who consent to randomisation will be randomised to implant-based and autologous breast reconstruction, whereas patients with strong preferences will be able to choose method. The study is designed as a superiority trial based on BREAST-Q and 124 participants will be randomised. In the preference cohort patients will be included until 62 participants have selected the least popular alternative. Follow-up will be 60-months. Embedded qualitative studies and within-trial economic evaluation will be performed.