This paper investigates variations in the tensile toughness of cracked steel fibre reinforced concrete (SFRC) subjected to corrosion damage, by means of a multiscale modelling framework. Experimental results were used to discretise the pull-out behaviour of single fibres using a spring-slider model, which were then upscaled to the composite level by means of a probabilistic fibre bundle approach. The model described the alteration of the residual tensile performance of the composite due to variations of the fibre-matrix bond strength and corrosion damage of the steel fibres, observed experimentally. This investigation supports recent hypotheses suggesting that corrosion damage of the steel fibres may not be the only mechanism responsible for the deterioration reported in cracked SFRC exposed to corrosive environments. The strengthening of the fibre-matrix bond over time may entail a decrease of the tensile toughness of the composite due to fibre rupture.