Polypropylene (PP) thermoplastic composites were fabricated using recycled carbon fibres (rCFs; recovered from composite parts) and waste CFs (wCFs; generated during post-manufacturing processes). Both staple CFs (average 60 mm long) were blended with staple PP resin fibres (60 mm long) and then converted into yarns prior to the composite fabrication using hot-pressed moulding technique. It is found that the composites fabricated from wCFs contained longer CFs (40 mm long) and exhibited better electrical and mechanical properties (conductivity: 10.75 x 10³ S m^-1; tensile strength 160 MPa and modulus 45 GPa) compared with the composites fabricated from rCFs. It was concluded and recommended that both composite materials could be used as cost-effective and heating elements in lightweight applications.