The influence of fibres on the structural behaviour and mechanical properties of concrete has been evaluated since long by several researchers. The significant improvement in the mechanical and flexural performance of fibre-reinforced structural elements has led to the acceptance and utilisation of fibre-reinforced concrete in numerous complex civil engineering applications. The contribution of synthetic fibres in significantly improving the residual flexural strength of concrete has been researched extensively, however, the influence of such fibres on the improvement of tension stiffening in concrete members has not been fully explored. This research experimentally investigates the influence of different volume fractions of synthetic fibres on the tension stiffening of concrete ties reinforced with glass fibre-reinforced polymer subjected to axial tension over time. Results indicated that the inclusion of synthetic fibres in concrete can significantly reduce the loss of tension stiffening of concrete resulting in an improved cracking behaviour of uniaxially reinforced concrete ties. Ties with FRC exhibited more cracks, smaller crack spacing, and lower crack width. The addition of synthetic fibres reduced the loss in tension stiffening of concrete over time by 27% and 46% in specimens with 5 and 10 kg/m3, respectively.