<p>Additive manufacturing (AM) has emerged as a transformative technology in modern manufacturing, offering significant advancements in design flexibility, material efficiency, and production speed. In the pursuit of enhancing part performance for industrial applications, this study aims to identify and evaluate the critical success factors relevant to fused deposition modelling (FDM)-based composite additive manufacturing. These factors were initially gathered through an extensive review of existing literature, supplemented by expert brainstorming sessions with professionals in the field. To refine and validate the identified factors, the Fuzzy Delphi (FD) method was employed. The finalised set of success factors was then prioritised using the fuzzy Stepwise Weight Assessment Ratio Analysis (SWARA) method. The findings reveal that hardware components—particularly 3D printing machines—play a pivotal role in determining the success of FDM composite manufacturing. Additionally, factors such as the mechanical properties of filler and fibre materials, interlayer adhesion, and printing parameters were found to have a significant influence on the quality and performance of the final printed products.</p> Graphical abstract <p>Hybrid Fuzzy Delphi–SWARA framework for prioritising success factors in FDM composite additive manufacturing</p>