A WMS (Warehouse Management System) is the software that runs the physical warehouse: goods receiving, storage locations, stock by bin, order picking, packing and loading.
What a WMS does
Where the ERP knows how much stock there is, the WMS knows where it is, shelf by shelf. It directs staff through handheld terminals and barcode scanners, sets picking sequences and tracks batches and expiry dates. In pharmaceutical distribution it’s the system that reads and verifies DataMatrix serialization codes: see what the 2027 deadline means for wholesalers.
WMS, ERP and transport
The three systems hand work to each other in sequence. The ERP records the order, the WMS prepares it, and the TMS or route planning software delivers it. The tricky handover is between warehouse and transport: the loading sequence has to follow the route sequence, or the driver ends up unloading half the van to reach the first stop. That’s why the route plan, once ready, needs to reach the warehouse, through an API or a file.
FAQ
Do you need a WMS to plan deliveries?
No. Route planning needs orders and addresses, which come from the ERP. A WMS starts to matter when picking volumes make it hard to prepare goods in the right order for loading.
Is a WMS the same as the ERP’s inventory module?
No. The ERP’s inventory module tracks quantities for accounting purposes; the WMS manages physical locations and what warehouse staff do. Many smaller businesses run with the first alone.