GS1 / UCC-128 Retail Compliance Label Guide

Retail compliance labels — also called GS1-128 labels or UCC-128 labels — are required by virtually every major U.S. retailer on all inbound shipments. They are the "passport" your shipment needs to enter a retailer's distribution center. Get them right and your product flows through receiving without issue. Get them wrong and you're looking at chargebacks, shipment delays, and sometimes refused deliveries — on every carton, on every shipment, until the configuration is fixed. This guide covers what GS1-128 labels are, what data they require, how requirements differ by retailer, and how to implement them correctly.

1. What Is a GS1-128 (UCC-128) Label?

A GS1-128 label is a standardized shipping label that uses the GS1-128 barcode symbology to encode supply chain data. GS1-128 replaced the older UCC-128 standard — the terms are used interchangeably in the industry, but GS1-128 is the current official name.

The label contains two types of data:

• Human-readable text: Information printed in plain text that warehouse staff can read without scanning — typically includes ship-to location, PO number, item description, and quantity
• Machine-readable barcodes: GS1-128 barcode(s) encoding the same data in a format scannable by DC receiving systems, sorters, and warehouse management software

Retailers use these labels to automatically receive, sort, and track your products through their supply chain — from inbound receiving at the DC all the way to store shelf replenishment.

2. GS1 Application Identifiers (AIs)

GS1-128 barcodes use Application Identifiers (AIs) to flag the type of data encoded. Each AI is a numeric prefix that tells the scanner what the following data represents.

AIData TypeExample(00)Serial Shipping Container Code (SSCC)Package identifier — unique per carton(01)Global Trade Item Number (GTIN / UPC)Product UPC encoded in the shipping label(10)Lot / Batch NumberRequired for food, pharma, and recall-sensitive items(11)Production DateYYMMDD format(17)Expiration DateYYMMDD format — required for dated products(30)Variable CountQuantity of units in the carton(37)Count of Trade ItemsNumber of items per case(400)Customer Purchase Order NumberPO number from retailer(420)Ship-to Zip Code (domestic)DC receiving zip code

3. Standard Label Zones

GS1-128 labels follow a standard four-zone layout. Each zone contains specific information required by retailers.

• Zone A (top): Ship-to / Ship-from information — DC name, address, city/state/zip
• Zone B (upper middle): Carrier routing, PO number, department number, item number
• Zone C (lower middle): Product description, quantity per carton, UPC
• Zone D (bottom): GS1-128 barcode(s) — typically SSCC and/or GTIN with AIs

While the zone structure is standardized, the specific data fields, positions, and barcode configurations required in each zone vary by retailer.

4. Retailer-Specific Requirements

This is where most suppliers run into trouble. Each major retailer publishes its own label specifications, and the differences between them are significant enough that a label built for Walmart will not work for Target or Kroger.

Walmart

• Requires SSCC-18 barcode in Zone D
• Specific field requirements for department, item number, and distribution center routing
• Must include PO number, GTIN, and quantity
• Labels are validated against Walmart's inbound compliance standards at the DC — defective labels trigger SQEP chargebacks

Target

• Requires GS1-128 on all carton labels
• PO number, item number, quantity per carton, and destination DC are required fields
• Physical barcode quality is enforced under the Perfect Order Program — barcodes that fail to scan generate $0.75 per defective carton chargebacks

Amazon (Vendor Central)

• Amazon has specific carton label requirements for vendor-fulfilled shipments to Amazon FCs
• Labels must include Amazon PO number, ASIN, and quantity per carton
• Amazon has transitioned from 1D to 2D barcode requirements in some categories — verify current specifications in Vendor Central

Kroger

• GS1-128 required on all inbound shipments across all banners
• Required fields include ship-to DC, PO number, item number, UPC, description, and quantity
• Lot/batch numbers required on applicable food and perishable items
• Labels typically required on two adjacent sides of each carton

Home Depot

• GS1-128 carton labels required for all shipments
• Requires SSCC barcode, PO number, item number, and quantity
• Must comply with Home Depot's Master Routing Guide specifications

Lowe's

• GS1-128 required on all shipping cartons
• PO number, SKU, quantity, and destination DC are required fields
• Pallet labels have additional requirements per Lowe's routing guide

5. GS1 Company Prefix Registration

To generate valid GS1-128 barcodes, you must have a GS1 Company Prefix registered with GS1 US. This is not optional — several major retailers, including Walmart and Kroger, require suppliers to have a direct GS1 relationship and will not accept barcodes generated by resellers.

• Register your company prefix at gs1us.org
• Your company prefix is embedded in your GTIN (product UPC) and SSCC (shipping container) numbers
• SSCC numbers must be unique per shipping carton — no two cartons should ever share an SSCC
• GTINs must be verified and up to date in the GS1 registry before shipments begin

6. Label Printing Best Practices

• Print quality: Use thermal transfer or direct thermal printers at 203 DPI minimum — 300 DPI recommended for reliable scanning
• Label stock: Use labels and ribbons specified for your printer and environment — heat, cold, and moisture affect barcode readability
• Barcode verification: Verify barcode quality using a GS1-compliant barcode verifier before printing production runs
• Template management: Maintain separate label templates per retailer — never use a generic template across multiple retail partners
• Version control: Update templates whenever a retailer publishes a compliance specification change
• Pre-shipment testing: Submit test labels to new retail partners for approval before the first shipment ships

How WarehouseQuote Helps

WarehouseQuote's technology platform generates GS1-128 compliant carton labels per each retailer's DC-specific specifications — automatically, at time of order processing.

• Retailer-specific label templates for 100+ retail partners maintained and updated in the WarehouseQuote platform
• SSCC number management with automatic incrementing to ensure unique carton identifiers
• Barcode quality verification built into the label generation workflow
• Label updates automatically triggered when retailer compliance specifications change
• ASN data feeds directly from label generation — eliminating the most common source of ASN/label mismatch chargebacks

Talk to our team to learn how WarehouseQuote manages retail compliance labeling for your operation.