This paper discusses how restorative justice (RJ) can be used to reduce prison overcrowding in Pakistan, using the mediation process. Slow processing of crimes and high levels of undertrial detention are the reason of overcrowding. The research is a mixed-methods study, which incorporates legal, prison data, and interviews with the stakeholders to determine whether RJ can alleviate overcrowding through diversion of viable cases out of the prison system. The results indicate that mediation can be used to minimise the remand time and prison admissions, especially in minor interpersonal and property cases. Nevertheless, it has minimal effects on more severe crimes like drug crimes. The success of RJ relies on the protection of the safeguards, such as voluntariness, protection of the victims, and judicial supervision. This paper concludes that RJ mediation, when done appropriately, can assist in decreasing overcrowding and enhancing the efficiency of the criminal justice system.