The evolution of retail supply chains into multi-echelon, omni-channel networks has made efficient inventory management increasingly critical, particularly in the grocery sector. Amid this transition, our sponsor—a leading U.S. grocery retailer—is shifting from localized inventory control to a globally optimized strategy and seeks to understand the value of dynamic Multi-Echelon Inventory Optimization (MEIO). This study quantifies the impact of dynamic MEIO and evaluates how varying policy update frequencies and service levels affect inventory value and holding costs across a complex distribution network. Utilizing Coupa’s Supply Chain Guru, we optimize safety stock placement for 61 SKUs across a network of 1 manufacturing facility, 5 hubs, and 25 spokes. We then evaluate the impact of varying inventory policy update frequencies (annual to weekly) and service levels on inventory value and holding costs. Our analysis reveals that implementing MEIO can unlock up to 40% inventory value reduction under conservative assumptions. Furthermore, a segmented approach, coupled with the selection of optimal update frequencies and service levels, explores potential inventory savings of up to 53%. Key insights include: (1) more frequent updates generally yield greater savings, particularly for products with high demand variability; (2) the cost benefits of more frequent updates become increasingly significant for products targeting high service levels; and (3) while achieving higher service levels necessitates substantial working capital, more frequent inventory policy updates can mitigate this investment. The project concludes with a scalable MEIO rollout framework, offering actionable guidance for grocery retailers seeking to enhance supply chain responsiveness and resilience through dynamic inventory management.