ABSTRACT Carbon nanotubes (CNTs) are among the most employed nanomaterials in developing new technologies. Their applicability requires a fundamental understanding of the chirality and defect effects on the mechanical properties. In this study, molecular dynamics (MD) simulations were performed to investigate the mechanical response of defective single-walled carbon nanotubes (SWCNTs) under tension loading. The Stones-Wales, monovacancy, and the divacancy reconstructions (585, 555777, and 555567777) defects were considered. In addition, we investigated the influence of the adaptive intermolecular reactive bond order (AIREBO) potential cut-off radii on the defect formation energy of SWCNTs. Our results reveal that the tensile strength properties are notably dependent on the chirality and defect configurations at strains over 8%. Energetically favourable defects have a high impact on the mechanical response of SWCNTs. A combination of certain defects may lead the control on the fracture pattern of the SWCNTs, which can significantly contribute to the designing of innovative nanostructures with tailored properties.