Pakistan, one of the world’s most water-stressed countries, is extremely vulnerable to climate change. This study analyzes the prospective effects of climate change on the rainfall in the Hub River Watershed (HRW), Sulaiman-Kirthar mountainous range of Pakistan. The projections of five global climate models (GCMs), from the Coupled Model Intercomparison Project phase 6 (CMIP6), were used. Analysis of future changes in rainfall patterns was performed under two shared socioeconomic pathways (SSPs). Results showed that the historical annual average rainfall was increasing in the HRW. The annual average rainfall is expected to decrease under SSP2–4.5 in HRW. However, under SSP5-8.5, an increasing trend over the next three decades is expected, particularly over the southern part of the HRB. The findings should further our knowledge of how climate change affects the Hub River Basin and motivate stakeholders and planners to develop the best mitigation plans.