LPN — Comprehensive Guide to License Plate Numbers in Warehousing

LPN — Comprehensive Guide to License Plate Numbers in Warehousing

The term LPN in logistics and warehouse management commonly refers to a License Plate Number — a unique alphanumeric identifier applied to an individual handling unit (pallet, case, tote, carton, or roll cage) so that the unit can be tracked and managed as a single entity throughout warehouse operations. LPNs are typically encoded on labels with machine-readable barcodes or RFID and linked in a Warehouse Management System (WMS) to inventory attributes such as item numbers, quantities, lot numbers, expiration dates, and storage locations.

At its core, an LPN decouples physical handling units from product identifiers (SKUs, GTINs, serial numbers), enabling operations to move, store, pick, and ship whole containers without repeatedly scanning every inner item. This reduces labor, speeds throughput, and improves accuracy while providing a persistent audit trail for the lifecycle of that handling unit.

How LPNs are structured and encoded

LPNs are usually designed as short alphanumeric strings that meet internal governance and system constraints. They may be system-generated sequential values, randomized identifiers, or structured codes that embed certain information (e.g., plant code, date, sequence). Labels typically include:

• A machine-readable symbol (1D barcode like Code 128 or GS1-128, or an RFID tag).

• Human-readable LPN text for manual verification.

• Optional additional data fields (item, quantity, lot, expiration, SSCC, destination).

Many operations adopt GS1 standards and use the SSCC (Serial Shipping Container Code) as the LPN when external traceability and cross-partner interoperability are required. Where interoperability isn’t essential, organizations may use proprietary LPN schemes as long as the WMS and other systems can interpret them consistently.

Common uses and benefits

• Receiving: Instead of scanning every item, inbound pallets or cases are assigned an LPN that represents the entire handling unit. The WMS links the LPN to the inbound purchase order and item information.

• Putaway and location control: LPNs simplify putaway by moving labels and scanning a single identifier for location updates, reducing errors and improving location-level accuracy.

• Picking and consolidation: When picking by case or pallet, pickers scan LPNs to confirm the correct handling unit. For multi-line orders consolidated into a tote, LPNs track contents during consolidation and transit.

• Inventory counts and cycle counting: LPN-based counting reduces counting time and supports reconciliation at the handling unit level.

• Traceability and audits: LPNs provide a transaction history that links handling unit movements, transformations (e.g., breakpack), and shipments for recall readiness and regulatory compliance.

Operational examples

A food distribution center receives a pallet of frozen goods. Each pallet gets an LPN label containing the SSCC, lot number, and expiration date. The pallet is put away into a cold storage bay. When a sales order requires several full pallets, the WMS instructs the forklift operator to pick by LPNs associated with the order, scan the LPNs at staging, and load them for shipment. If a recall occurs, the LPN history enables the warehouse to identify which orders received units from the affected lot quickly.

Integration considerations

LPNs have value only when they are integrated into core systems. A WMS must be configured to generate or accept LPNs, associate LPNs with product attributes, and manage the lifecycle (creation, split, merge, retirement). Integrations with ERP and TMS ensure order, invoicing, and shipping records reference the same LPNs for end-to-end visibility across supply chain partners.

Limitations and governance

Effective LPN usage requires governance: unique generation rules, label standards, and exception handling for damaged or missing labels. Poor label quality, inconsistent assignment, or duplicate LPNs can undermine accuracy. Organizations must also consider data retention, privacy, and how LPNs map to lot and serial-level traceability requirements.

Summary

LPN is a foundational element of modern warehouse operations. When designed and implemented well, LPNs streamline handling, improve accuracy, and provide traceability while enabling automation and higher labor productivity. Whether using proprietary codes or GS1 SSCCs, the key is consistent rules, reliable labeling, and integration with WMS and upstream/downstream systems.