<p>This study focuses on developing region-specific seismic attenuation relationships for North-west Iran, a tectonically active area prone to frequent and destructive earthquakes. By analyzing a robust dataset of seismic events, we identify breakpoints in attenuation behavior at distances of 85 km and 175 km, attributed to crustal features such as the Moho and Conrad discontinuities. Using nonlinear optimization and inversion methods with explicit parameter bounds, we estimate frequency-dependent parameters, including geometric spreading coefficients, quality factor (Q), and magnitude-dependent terms. The geometric spreading coefficients for velocity data show slight variations across frequencies, reflecting the complex crustal structure in the region. Negative values of these coefficients indicate a significant velocity contrast at the Moho discontinuity, leading to substantial energy reflection. The observed amplitude decay trend remains consistent between breakpoints, with a notable change at approximately 175 km, likely due to the superposition of reflective phases from the Conrad and Moho discontinuities and multiple reflections within the S-wave window. Crustal stratification ensures continuous energy reflection, resulting in geometric spreading attenuation coefficients that exceed theoretical predictions. These empirically derived coefficients are intended for regional hazard assessment and may not be directly portable to other tectonic settings. The calculated average shear wave quality factor (Q) for the region is empirical and reflects the area’s structural characteristics and high seismicity. The findings provide practical insights for seismic hazard assessments and support the design of resilient infrastructure in North-west Iran.</p>