Amazon ASN: Workflow, Compliance & Chargeback Prevention

If you ship to Amazon, you already know one thing: Amazon doesn’t leave room for guesswork. Every shipment has to arrive with clean data, correct labels, and perfect alignment between what you send and what Amazon receives. That’s where the ASN (Advanced Shipping Notice) comes in.

Your ASN tells Amazon exactly what’s inside your cartons and pallets before they even arrive. It includes PO numbers, SKU-level details, SSCC-18 labels, tracking information, and everything else Amazon needs to prepare for receiving.

When the ASN is accurate, your freight moves quickly through the FC. When it isn’t? Delays, disputes, exceptions, and chargebacks follow, sometimes all at once.

In this guide, we’ll simplify Amazon’s ASN workflow, explain compliance requirements, break down common errors, and share the best practices vendors use to stay penalty-free.

What is an Amazon ASN?

An Advanced Shipping Notice is an electronic document (EDI 856 or Vendor Central ASN form) that describes:

• Purchase Order number
• SKU/ASIN identifiers
• Carton, pallet, and unit counts
• SSCC-18 labels and carton IDs
• Carrier details and tracking
• Ship-from/ship-to info
• Pack structure (case > inner packs > units)

Amazon requires vendors to submit the ASN before the shipment arrives at the fulfillment center, and in many cases before the carrier even picks up the freight, to ensure timely and accurate receiving.

Think of it as your shipment’s “digital blueprint.” Amazon uses this data to:

• Schedule dock appointments
• Assign FC labour
• Validate quantities and barcodes
• Match scanned cartons to PO expectations
• Update inventory accurately and on time

Serial Shipping Container Code (SSCC-18) Labels for Amazon Shipments

The SSCC-18 (Serial Shipping Container Code) is an 18-digit identifier Amazon uses to track cartons and pallets throughout the receiving process. Printed as a GS1-128 barcode, it’s scanned at every checkpoint, making it a critical part of accurate ASN-to-carton matching.

• What it is:
  A globally recognized 18-digit code that uniquely identifies every shipping carton or pallet.
• Why Amazon needs it:
  SSCC-18 links your physical shipment to the data in your ASN. When Amazon scans the barcode, it instantly confirms the carton's identity and contents.
• Why it matters:
  Correct SSCC-18 values help Amazon match your cartons to your ASN, reducing receiving delays and avoiding carton-content accuracy chargebacks.
• Your responsibility:
  Ensure every carton or pallet has:
  
  • A valid SSCC-18 number and GS1-128 barcode
  • A barcode that exactly matches the number transmitted in your ASN
  • No duplicated, reused, or missing SSCC-18 labels

Using SSCC-18 labels correctly keeps your shipments flowing smoothly through Amazon’s network and helps prevent avoidable exceptions and chargebacks.

Note:  Want to see how ASN processes work at Walmart? Read our full Walmart ASN Guide.

Why ASN accuracy is critical for Amazon Vendors

Amazon’s receiving operations rely on barcode automation. Every carton entering an Amazon FC is scanned and matched against the ASN. Any inconsistency triggers an exception. 

Missing, late, or inaccurate ASNs are automatically flagged under Amazon’s Receive Process Compliance standards, often resulting in avoidable chargebacks.

If your ASN is inaccurate, you may face:

Operational disruptions

• Dock holds
• Receiving delays
• Shipment misrouting within FC

Financial penalties (chargebacks)

• ASN Accuracy Chargeback
• PO Mismatch Chargeback
• Invalid or Missing Label Chargeback

Vendor performance impact

• Reduced reliability score
• Increased deductions
• Higher likelihood of manual checks

Amazon’s supply chain moves fast. A late, missing, or mismatched ASN slows operations and immediately impacts your profit margin.

How to submit an ASN to Amazon

You can submit ASNs through:

A. Vendor Central (Manual Submission)

While Amazon supports both manual ASN entry in Vendor Central and automated EDI 856 submissions, high-volume vendors are strongly encouraged, and sometimes required, to transmit ASNs via EDI to maintain compliance and prevent timing-related chargebacks.

Steps:

1. Go to Orders → Purchase Orders.
2. Choose the PO you’re fulfilling.
3. Select Create ASN.
4. Enter shipping details:
   • Ship-from address
   • Carrier name + tracking
   • Carton count and pallet count
5. Enter line-level details:
   • Each SKU/ASIN
   • Units per carton
   • Pack structure (if applicable)
6. Assign or upload SSCC-18 carton IDs.
7. Review and submit before the shipment leaves your dock.

This method is more labour-intensive and prone to human error.

B. EDI 856 (Automated Submission)

EDI is Amazon’s preferred method because it reduces entry errors and syncs directly with your ERP/WMS.

A valid EDI 856 contains required segments such as:

• BSN – Transaction set purpose
• HL – Hierarchical levels (Shipment → Order → Pack → Item)
• LIN – Item identification
• SN1 – Item quantity
• REF – SSCC-18 carton ID
• DTM – Dates/times
• TD5 / TD1 – Carrier and packaging details

To maintain compliance:

• Ensure your system generates SSCC labels correctly
• Confirm that each EDI “pack” segment maps to a real carton
• Send the ASN before pickup or departure

EDI mistakes often result in multiple overlapping chargebacks because Amazon cannot accurately interpret the data.

Amazon ASN Requirements

Amazon has specific rules for every vendor shipment. Common requirements include:

SSCC-18 label on every carton

Scannable and unique, linking the physical carton to the ASN.

ASN must match PO exactly

• ASIN
• SKU
• Quantity
• Case packs
• Units per carton
• Total carton count

ASN must reflect the correct shipping method

• Small parcel
• LTL / FTL
• Direct Fulfillment (if applicable)

All tracking numbers must be included

Amazon uses this to reconcile delivery data with the ASN.

Pallet structure must match reality (if palletized)

Incorrect pallet-level data often leads to FC receiving exceptions.

Common Amazon ASN Errors (and why they happen)

Even experienced vendors can be affected by Amazon ASN deductions. Here are the most frequent issues:

1. Carton/SKU mismatch

Units inside the carton don’t match the ASN pack data.

Cause: Poor pick/pack accuracy or incorrect WMS data.

2. Incorrect or missing SSCC labels

Cartons arrive without readable SSCC-18 barcodes.

Cause: Printer errors, duplicate labels, labels falling off, or wrong label placement.

3. ASN submitted late

Amazon receives your shipment before the ASN.

Cause: Carrier pickup before ASN submission or internal delays.

4. Duplicate ASNs

Two ASNs were submitted for the same PO shipment.

Cause: WMS/EDI misconfiguration or human error.

5. Wrong PO linked

Amazon cannot associate the carton with the shipment.

Cause: Wrong PO number or reference mismatch.

6. Incorrect pack structure

Inner packs or units per case do not match the ASN.

Cause: Improper case pack documentation or inconsistent packaging.

Why Amazon issues chargebacks for ASN mistakes?

Amazon enforces strict compliance. Common ASN-related chargebacks include:

• ASN Accuracy Chargeback – Data mismatch between carton and ASN
• PO Mismatch Chargeback – Wrong PO referenced
• Invalid or Missing Label Chargeback – SSCC missing or unreadable
• Routing/Delivery Chargeback – If the ASN causes receiving delays

These deductions reduce your margin and often go unnoticed until the weekly or monthly statements.

To minimize impact:

• Validate carton-level data before shipment
• Ensure labels match ASN pack data
• Confirm tracking numbers and pallet structure
• Keep internal logs for proof in case of disputes

Best Practices for Amazon ASN Compliance

Use these practices to keep your ASN accuracy near 100%:

Ensure items match PO expectations before sealing cartons.

Manual label creation introduces duplications and inconsistencies.

Use handheld scanners or automated systems to verify label accuracy.

Late ASNs are one of the most frequent issues Amazon flags.

Avoid human entry errors by connecting systems directly.

Ensures every PO is validated the same way every time.

Amazon ASN Compliance Checklist

This checklist helps reduce errors across operations and supports compliance at scale.

How iNymbus Helps You Resolve Amazon ASN Chargebacks

Managing Amazon ASN chargebacks can be stressful, especially when you’re juggling high volumes, carton-level details, and strict SSCC‑18 requirements. That’s where iNymbus makes a difference.

Instead of creating ASNs, iNymbus automatically matches your shipment and ASN data against Amazon’s portal to identify any incorrect or preventable chargebacks. When an invalid deduction is detected, the system prepares and submits accurate dispute claims on your behalf, helping you recover revenue quickly and efficiently.

With iNymbus, your team benefits from:

• Accurate chargeback identification - we flag only invalid deductions that can be disputed. 
• Streamlined dispute process  – disputes are submitted directly in Amazon Vendor Central.
• Reduced manual effort – focus on exceptions, not paperwork.
• Faster recovery – get revenue back from incorrect chargebacks sooner.

By ensuring every disputable chargeback is handled promptly and accurately, iNymbus helps vendors protect their margins, reduce manual workload, and maintain better compliance with Amazon’s ASN and receiving rules.

Conclusion

An Amazon ASN is a critical part of the vendor compliance ecosystem. Accurate ASN submissions prevent receiving delays, reduce chargebacks, and protect your profitability.

By understanding Amazon-specific requirements, following best practices, validating carton-level accuracy, and strengthening your workflow, you can significantly improve your vendor performance score and avoid costly deductions.

Frequently Asked Questions

A digital shipment notification that tells Amazon exactly what items, quantities, and cartons to expect before the shipment arrives.

Before the shipment leaves your facility, Amazon must have it before physical delivery.

Data mismatches, missing SSCC-18 labels, incorrect pack structure, late ASNs, or wrong PO information.

Yes. EDI 856 is Amazon’s preferred format because it reduces the need for manual entry and minimizes submission errors.

Scan all cartons before shipping, automate SSCC generation, and integrate your systems for accuracy.