In this work, we demonstrated a novel and facile approach to synthesising anode materials for sodium-ion batteries (SIBs). Briefly, 1,3,5-tris(4-aminophenyl)benzene and terephthalaldehyde were used to form porous covalent-organic frameworks (COFs) as precursors for the anodic materials. A simple carbonisation of the COFs at elevated temperatures produced nitrogen-doped, carbon-based materials with interconnected, highly-porous network structures. Of all the carbonisation temperatures experimented, the carbonisation temperature of 800 °C resulted in the best-performing material. This material had a reversible capacity of 303 mA h g−1 at 100 mA g−1 and exhibited excellent stability over 1000 cycles at 100 and 1000 mA g−1 respectively without the aid of any conductive additives. These results offer new possibilities to the field of disordered carbons used in SIBs.