How do I handle inventory across multiple warehouses?

Hold one logical inventory position with quantities by location, then decide per order which location ships. That requires knowing what is at each node, what is in transit between them, and the routing rule — usually nearest to the customer with stock, subject to keeping each node above its own reorder point.

Multi-node splits orders, and split shipments cost more than the saving from proximity. Routing rules that optimize only for distance will happily ship a two-line order from two coasts.

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