SKU Migration

Act as a highly experienced professional seller and inventory management expert on Amazon US Seller Central. You possess expensive, in-depth knowledge of Amazon's catalog and listing policies, particularly concerning unique identifiers.

A seller has a mature inventory of listed products (ASINs) that have been active and selling for several months. Their initial Seller SKUs (Stock Keeping Units) were created hastily and now lack consistency, making internal inventory tracking and reordering inefficient. The seller urgently needs to revise these existing, active SKUs to conform to a specific, consistent naming convention (e.g., BRAND-MODEL-COLOR-SIZE-V01).

Provide a definitive, step-by-step, and policy-accurate answer to the following critical question:

'Is it technically possible and/or permissible within Amazon policy for a seller to directly edit and revise the SKU name of an existing, actively-selling product offer that has sales history?'

If the direct revision is impossible (as is commonly understood), the response must then provide a comprehensive, best-practice workaround. This workaround should detail the exact process to effectively 'change' the SKU, including specific considerations for:

1. FBM (Fulfilled by Merchant) Inventory: The simplest method to transition.
2. FBA (Fulfilled by Amazon) Inventory: The complexities involving FNSKUs, existing inventory in Amazon fulfillment centers, and the necessity of new shipment plans.
3. Sales History Preservation: How the ASIN retains its performance history despite the SKU change.
4. Buy Box Transition: Ensuring a smooth transfer of the 'offer' without losing the Buy Box eligibility."

---

This is a critical inventory management issue. As a seasoned Amazon inventory expert, I can provide the definitive answer and the necessary workaround.

The definitive answer is an emphatic NO 🚫.

It is not technically possible and not permissible to directly edit or revise the Seller SKU (Stock Keeping Unit) of an existing, actively-selling product offer with sales history on Amazon Seller Central.

Why SKUs Are Immutable

A Seller SKU is Amazon's primary key for your specific offer. It is a permanent, static identifier used to link your inventory, sales data, accounting records, returns, and fulfillment method (FBM or FBA) to the parent ASIN (Amazon Standard Identification Number). Changing the SKU would break this critical relational database structure, which is why Amazon locks it upon creation.

The Best-Practice Workaround: The SKU Migration

Since you can't edit the old SKU, you must perform an SKU Migration (or "SKU Refresh"). This involves creating a new offer for the same ASIN using your desired convention and then safely retiring the old offer. The ASIN retains the history, while the new SKU takes over sales.

Step 1: Create the New Offer

1. Record Details: Document the ASIN, current price, condition, and Fulfillment Channel (FBA/FBM) of the listing with the old SKU.
2. Add Product: In Seller Central, navigate to Inventory $\rightarrow$ Add a Product.
3. Search by ASIN: Search for the existing product using the ASIN.
4. Create Offer: Click "Sell yours" and on the offer page, enter your new, standardized SKU (e.g., BRAND-MODEL-COLOR-SIZE-V01) into the Seller SKU field.
5. Match Details: Input the exact same price, condition, and product details as the old offer.

Step 2: Critical Inventory Transition (FBM vs. FBA)

1. FBM (Fulfilled by Merchant) Inventory: The Simplest Transition

The FBM process is straightforward as inventory is managed externally:

1. Zero Out Old SKU: In your Manage Inventory page, find the old SKU and set its quantity to 0.
2. Activate New SKU: Set the quantity of the new, compliant SKU to your actual available stock.
3. Wait for Transition: Allow a few minutes for the system to process the change and ensure the new SKU has taken over the active offer status.
4. Delete Old Offer: Once sales are successfully routing through the new SKU, find the old SKU, click the dropdown menu, and select Delete product and listing (this only deletes your offer, not the ASIN).

2. FBA (Fulfilled by Amazon) Inventory: The Complex Transition

FBA inventory is permanently linked to an FNSKU, which is generated based on the original SKU. You cannot transfer existing physical stock from one SKU to another in Amazon's warehouse.

The best-practice method is Sell-Through and Restock:

1. Leave Old SKU Active: Do NOT delete or zero out the old FBA SKU. Let the inventory associated with it sell completely out.
2. Create New FBA Plan: Use the newly created SKU to generate a new FBA Shipment Plan. This action generates a new, unique FNSKU for the item.
3. Label New Units: Start labeling your future restock units with the new FNSKU generated by the new SKU's shipment plan.
4. Ship New Inventory: Ship your new, correctly labeled stock to Amazon.
5. Phased Sell-Off: The old SKU inventory will sell off, and as it hits zero, the new SKU's stock will become the active offer.
6. Final Deletion: Once the old SKU's FBA inventory quantity reaches zero (and stays there), you may safely use Delete product and listing on the old SKU.

Step 3: Sales History and Buy Box Security

3. Sales History Preservation

The good news is that performance history is secure:

• ASIN is King: The ASIN holds the product's entire history, including customer reviews, product rank, BSR (Best Seller Rank), and primary sales data.
• Inheritance: When you delete the old SKU offer and launch the new one, the new SKU instantly inherits the full weight of the ASIN's historical performance. Your product ranking is not jeopardized by this process.

4. Buy Box Transition

• Seamless Transfer: Since you are creating a second, identical offer on the same ASIN, the new SKU (once active and in stock) will typically take over the Buy Box immediately, especially for FBM when the old stock is zeroed out.
• No Competitive Risk (Self): Because both SKUs belong to you (the same seller), your two offers will essentially compete against each other for the Buy Box for a brief period if they are both active. As long as the price and fulfillment channel are the same, the transfer is usually seamless. For FBA, the system simply depletes one offer then starts selling the other. You will not lose Buy Box eligibility during this internal migration.