Detecting change points in long-term rainfall patterns is crucial for understanding climatic shifts and formulating water resource management strategies, particularly in arid regions. This study investigates changes in annual and seasonal rainfall across 12 grid points in the Thar Desert, Rajasthan, using three statistical tests: Pettitt’s test, the Standard Normal Homogeneity Test (SNHT), and Buishand’s test. The results reveal significant rainfall variability, with key breakpoints identified in 1988–1991 and 2009 across multiple grids. Pettitt’s test primarily detected abrupt shifts in 1991 and 1988, suggesting possible changes linked to regional climatic events. SNHT and Buishand’s tests consistently identified 2009 as a critical year, indicating more gradual, region-wide shifts in rainfall patterns, potentially tied to larger climatic anomalies or anthropogenic influences. The presence of heterogeneity in these periods suggests significant alterations in rainfall trends, which may impact groundwater recharge, agricultural productivity, and water resource planning in the region. These findings underscore the importance of understanding both abrupt and gradual changes in rainfall for developing effective climate adaptation strategies in arid environments. Further cross-validation with other tests and climate model data could enhance the robustness of these findings and provide insights into the underlying causes of these detected shifts.