Urban Heat Island (UHI) conditions intensify urban warming, increasing cooling energy demand and reducing outdoor comfort. This study evaluates microencapsulated organic paraffin phase change material (PCM, MPCM28D) as a sand-replacement additive in rigid concrete pavement for sidewalk applications as a scalable UHI mitigation strategy. Thermal characterization confirmed the material’s latent heat storage capacity, while compressive strength tests assessed mechanical performance relative to Texas Department of Transportation (TxDOT) sidewalk concrete requirements. Indoor testing under an 8-hour heating-cooling cycle produced surface temperature reductions of up to 2–4 ÅãC for the 10% PCM mixture, and similar trends were observed in 8-hour outdoor exposure tests, with a maximum reduction of 4 ÅãC. A Six-month sidewalk pilot with one control slab and five cooling treatments ; 5% PCM, reflective finishes, and hybrid configurations, showed the best cooling performance in slabs incorporating 2.5% PCM with diamond grinding or sandblasting. These hybrid treatments provided the most stable temperature reductions, as measured by the Monthly Cooling Benefit Index (MCBI). Overall, the results confirm that sandreplacement PCM combined with surface enhancement is a viable approach for improving the thermal performance of urban concrete pavements.