<p>This work investigates the feasibility of applying single point incremental forming (SPIF) to polycaprolactone (PCL) sheets manufactured via fused filament fabrication (FFF). An experimental campaign was conducted for evaluating the response of FFF-printed sheets under SPIF plastic deformation, considering the influence of the spindle speed and step down. Formability and failure, forming forces, temperature, surface roughness, as well as shape accuracy were analysed on the testing pyramidal geometries. Strain states were evaluated with respect to forming limits assessed in prior research. In addition, a qualitative comparison with compression-moulded PCL sheets was carried out to determine the influence of the manufacturing route. Results showed that all FFF-printed sheets were formed without fracture within the tested conditions, exhibiting stable plastic behaviour under incremental deformation. Process parameters affected forming forces, temperature, and surface quality, while fair geometric accuracy and thickness distributions were achieved. The comparison with compression-moulded sheets suggested a similar forming response under the analysed conditions. Based on these results, the feasibility of the hybrid FFF + SPIF approach was explored. As a proof of concept, the hybrid process was successfully applied to the manufacturing of a customized cranial geometry, showing its potential to achieve the required anatomical accuracy and geometric fit for patient-adapted shapes for biomedical applications.</p>