An Advanced Shipping Notice (ASN) is an electronic document sent by suppliers to notify recipients about an upcoming delivery before it arrives. The ASN contains detailed information about the shipment including contents, quantities, packaging details, expected arrival time, and tracking numbers, allowing warehouses to prepare for efficient receiving and putaway.

It's knowing what's coming before it arrives and being ready for it.

Why ASNs Matter

Traditional receiving is reactive. Delivery truck appears at your dock, you discover what's inside, scramble to find space, slowly process everything. Staff are caught off guard, receiving takes hours, incoming stock blocks workflow, and inventory accuracy suffers from rushed data entry.

ASNs transform receiving from chaotic to controlled. You know exactly what's arriving, when, and in what quantities. Pre-allocate storage locations, schedule labour appropriately, prepare receiving areas, and process shipments 50-70% faster. The efficiency gains are substantial.

What's in an ASN

Supplier information: Who's sending the shipment, contact details, supplier reference numbers.

Shipment details: Tracking number, carrier name, expected delivery date and time, origin location.

Product information: SKU numbers, product descriptions, quantities per SKU, unit of measure (eaches, cases, pallets).

Packaging details: Number of cartons/pallets, dimensions, weight, how products are packed (individual boxes, master cartons, pallet configuration).

Serial/batch information: For products requiring traceability, includes serial numbers, batch numbers, lot numbers, expiry dates.

Purchase order reference: Links shipment to original PO, enabling verification of ordered vs shipped quantities.

Special instructions: Handling requirements, quality control needs, documentation requirements.

The ASN Process

Supplier prepares shipment and generates ASN electronically. ASN transmits to recipient's warehouse management system via EDI, API, or XML. WMS receives ASN and creates expected receipt in system. Warehouse staff review upcoming deliveries and prepare accordingly.

When shipment arrives, staff scan products against ASN. System compares scanned items to ASN data: immediate visibility if anything's missing or wrong. Once verified, goods move to putaway using pre-allocated locations. Inventory updates automatically in real-time.

If discrepancies exist, system flags them immediately. Receive 95 units when ASN said 100? You know instantly rather than discovering it weeks later during cycle counting.

Benefits

Faster receiving: Pre-planning eliminates guesswork. Staff know what's arriving and process shipments 50-70% faster. One 3PL reduced average receiving time from 45 minutes per pallet to 15 minutes with ASN implementation.

Improved accuracy: Scanning against ASN catches errors immediately. Supplier ships wrong quantity or product? You know before it enters inventory. Protects inventory accuracy from cascading errors.

Better labour planning: Know exactly when deliveries arrive and how much labour they require. Schedule staff accordingly rather than maintaining excess capacity "just in case."

Optimised space utilisation: Pre-allocate storage locations based on incoming products. No more blocking aisles with pallets whilst figuring out where they go.

Enhanced visibility: Real-time shipment tracking. Know when delayed deliveries affect operations. Update customers proactively if their order depends on incoming stock.

Reduced paperwork: Electronic data eliminates paper packing lists, manual data entry, and filing. Less administration, fewer errors.

Faster stock availability: Goods move from receiving to pickable inventory faster. Reduce dock-to-stock time from hours to minutes.

ASN Standards

EDI 856: The most common ASN format in supply chain. Structured electronic data interchange standard ensuring compatibility between trading partners. Detailed, comprehensive, but requires EDI infrastructure.

XML/API: More flexible, modern approach. Easier integration with cloud-based WMS platforms. Growing in popularity, especially for smaller businesses.

GS1 standards: Global standards for product identification and ASN formatting. Ensures consistency across international supply chains.

Custom formats: Some businesses use proprietary formats, but these limit trading partner compatibility. Avoid if possible.

Implementation Challenges

Supplier compliance: Not all suppliers support ASNs. Small suppliers might lack technology or willingness to send them. You might need to provide templates, training, or incentives.

Data quality: ASN is only valuable if accurate. Suppliers sending incorrect data create more problems than no ASN at all. Establish data quality standards and monitor compliance.

System integration: Your WMS must receive, parse, and act on ASN data. Legacy systems might struggle. Modern cloud-based WMS platforms handle this seamlessly.

Change management: Staff must shift from "open boxes and see what's inside" to "scan and verify against ASN." Requires training and process changes.

Timing accuracy: ASN sent too early (shipment delayed) or too late (arrives before ASN) reduces value. Establish timing standards with suppliers.

Best Practices

Mandate ASNs for key suppliers: Make it non-negotiable for high-volume suppliers. Build ASN capability into supplier onboarding process.

Provide clear requirements: Document exactly what information you need, in what format, and when. Don't assume suppliers know.

Monitor and report compliance: Track which suppliers send ASNs, data accuracy rates, timing adherence. Share reports with suppliers regularly.

Reward compliance: Faster payment terms, preferred supplier status, or other incentives for suppliers consistently sending quality ASNs.

Use ASN data proactively: Don't just receive shipments faster: use ASN data for labour planning, space management, and inventory forecasting.

Validate upon receipt: Always verify physical goods match ASN data. Don't assume accuracy. Scanning takes seconds and prevents costly errors.

Close the loop: Send acknowledgements back to suppliers confirming receipt. Report discrepancies promptly. Two-way communication improves accuracy.

ASN vs Other Documents

ASN vs Packing List: Packing list arrives with goods (paper in box). ASN arrives electronically before goods. ASN allows preparation; packing list doesn't.

ASN vs Bill of Lading: BOL is legal document for freight transport. ASN is operational document for warehouse receiving. Both can exist for same shipment.

ASN vs Purchase Order: PO says what you ordered. ASN says what supplier actually shipped. They should match but often don't.

Industry Adoption

Retail: Heavy ASN adoption. Major retailers (Walmart, Tesco, Amazon) mandate ASNs from suppliers. No ASN often means no business relationship.

Manufacturing: Widespread use, especially in automotive and electronics where just-in-time manufacturing depends on receiving accuracy.

Fashion/apparel: Growing adoption. Complex SKU matrices (size, colour, style) benefit enormously from ASN accuracy.

Food and beverage: Critical for perishables. ASN includes expiry dates and batch tracking essential for FIFO management.

Small businesses: Lagging adoption due to cost and technical barriers. Cloud WMS solutions are changing this, making ASNs accessible to smaller operations.

Getting Started

Identify high-volume suppliers first. Focus on 20% of suppliers representing 80% of inbound volume. Start there rather than trying to onboard everyone simultaneously.

Choose ASN format. EDI 856 for large trading partners with EDI capability. XML/API for smaller, more agile suppliers. Document requirements clearly.

Update your WMS to receive and process ASNs. If using legacy system, this might require development. Modern cloud WMS typically includes ASN capability out-of-box.

Train receiving staff on new workflow. Scanning against ASN, handling discrepancies, updating system correctly. Change management matters.

Pilot with one supplier. Work out kinks before expanding programme. Learn what information you actually need versus nice-to-have.

Measure results. Track receiving time, accuracy rates, labour efficiency, dock-to-stock time. Quantify improvements to justify expansion.

ASNs aren't glamorous. They're invisible to customers. But they're foundational to warehouse efficiency. Operations without ASNs are flying blind, reacting constantly to surprises. Operations with ASNs are prepared, efficient, and accurate.

The difference shows in your inventory accuracy, labour productivity, and customer satisfaction. Invest in getting suppliers onboard, and the returns compound daily.