This study examines the impact risk consequences due to asteroid disruption by a deflection mission. We use an Apophis-like scenario with a Nuclear Explosive Device (NED) deflection mission in our case studies. A Monte Carlo framework samples asteroid physical properties from probabilistic distributions based on the current knowledge of Apophis, and samples orbital states from an archival orbit solution reflecting Apophis’ 2.7% peak impact probability. Asteroid disruption is modelled at deflection time and the fragments are propagated forward to calculate if and where they impact the Earth. NASA’s Probabilistic Asteroid Impact Risk (PAIR) model estimates the impact damage in terms of affected population, and the overall scenario impact risk is calculated. Multiple case studies are explored to generate comparative data for scenarios where the asteroid is not altered, is always disrupted, or is conditionally disrupted with deflection impulse. The analysis shows that disruption increases impact risk for this Apophis scenario significantly. Even though deflection missions may cause disruption, a sufficiently strong deflection mission can be effective as risk decreases from its post-disruption peak with increasing deflection strength. Results also point to the dependence of risk changes on physical properties. Objects with a fraction of Apophisâ\euro™ mass will result in less risk when disrupted. We recommend that disruption analysis should be a critical factor in future asteroid mitigation considerations and suggest future research avenues of interest to mission design as well as planetary sciences.