12 Sorts of Amazon FBA Inventory
1. Fulfillable Inventory
Fulfillable inventory, also called available inventory or FBA inventory on-hand, refers to "stock stored at Amazon's fulfillment centers that can be picked, packed, and shipped to customers."
The in-stock rate calculation depends on the percentage of time replenishable FBA products maintain stock during the last 30 days, weighted by sales volume over 60 days.
Formula: (% in stock of ASIN #1 for 30 days × 60-day sales velocity) + (% in stock of ASIN #2 × sales velocity) / total 60-day sales velocity = In-Stock Rate
Example: Product 1 at 80% stock with 3.0 velocity, Product 2 at 70% with 2.0 velocity = 76% stock rate, considered fair by Amazon.
Tools like Seller Central's Inventory Performance Dashboard help optimize fulfillable inventory management.
2. Unfulfillable Inventory
Unfulfillable inventory refers to ineligible inventory that Amazon rejects during quality inspection. "Each item in the shipment will undergo quality inspection (and quantitative inspection)."
Damaged or unsuitable items receive removal notifications. Sellers have 30 calendar days to submit removal orders with options to repackage, liquidate, or return items.
Removal fees vary by product size and weight. Standard items under 500g cost €0.25-€0.55, with additional charges for heavier items. Amazon covers shipping damage during their care, per the FBA Shipping Reimbursement policy.
3. Backorder Inventory
Backorder inventory (inbound inventory) includes products currently in transit or being processed at fulfillment centers, showing estimated arrival quantities.
Status changes from inbound to receiving upon arrival, then to active/in-stock. Managing inbound stock directly impacts utilization rates and maximum inventory limits.
TIP: Using automated just-in-time mechanisms prevents excess inbound stock by analyzing historical sales data or comparable product performance.
4. Reserved Inventory
Reserved inventory consists of units awaiting delivery, undergoing FC transfers, or being processed for verification. Despite Amazon's claims, reserves can negatively affect utilization rates.
Formula for maximum shipping quantity: Restock limit – FBA Inventory – Open Shipments – Reserved inventory = Maximum Ship Quantity
Recent policy updates include tighter capacity limits, especially during peak periods like Prime Day. Monitoring reserved levels prevents reaching restock limits and protects IPI scores, sales, and rankings.
5. Extra Inventory
Extra inventory refers to unutilized or unsold goods that lose value over time. Amazon considers inventory excessive when:
- Minimum one unit exceeds 90 days old
- Inventory holds more than 90 days' supply
- Storage costs exceed potential selling value
TIP: Check your Inventory Health Report regularly for aging products. Taking action prevents warehouse storage beyond three months, when long-term storage costs activate, maintaining high IPI scores.
Dangers of excess inventory:
- Lower Amazon IPI scores
- Increased slow-seller products
- Cash flow issues
Movement strategies include Amazon Outlet Deals, Lightning Deals, liquidation orders, or removal orders.
6. Amazon Stranded Inventory
Stranded inventory cannot be sold due to unavailability. Common causes include:
- Listing, pricing, or information errors
- Inactive or suspended listings
- Products marked out of stock despite FBA availability
- New product additions needing 24-hour catalog updates
- Stock quantity matching recent customer orders
- Limited product restrictions
- Expired product designations
- Missing brand approval requirements
Resolution: Check the stranded inventory report, correct errors, relist the item. For unsellable goods, create a removal order for disposal or return.
7. Buffer Stock
Buffer stock (safety stock) represents extra inventory kept at FBA or warehouses to handle unexpected shipping delays. Sellers frequently restocking at low levels should maintain buffer stock for preparedness.
TIP: Calculate ideal buffer levels using sales data and weighted averages of remaining stock days, accounting for seasonal effects when possible.
8. Anticipation Inventory
Anticipation inventory addresses seasonally-driven demand spikes. "Sellers need to purchase sufficient swim trunks to be able to sell more summer clothing, such as swimwear."
Plan inventory around major selling dates: Mother's Day, Father's Day, Valentine's Day, Prime Day, Black Friday/Cyber Monday, and holiday seasons. Leveraging analytics to prioritize top SKUs and accurate demand forecasting proves crucial for effective management.
9. Amazon Commingled Inventory
Commingled inventory pools products sharing manufacturer barcodes. "This option is typical for resellers and retail and less common for private label sellers."
Why commingled works: Once activated in seller central, products don't require individual labels. FBA stores items together, and Amazon ships from commingled stock. Sellers receive credit for orders, shortening delivery times.
Trade-offs: No control over product authenticity or quality; counterfeit complaints are difficult to defend.
Amazon requires commingled items to be new, non-perishable, non-expiring, non-hazardous, with matching UPC/EAN/ISBN codes and proper packaging labels.
Alternative: Use FNSKU (Fulfillment Network Stock Keeping Unit) barcodes for item tracking. Amazon generates FNSKU automatically upon FBA shipment creation, or sellers can use the FBA Label Service for per-item charges.
10. Amazon Meltable Inventory
Meltable inventory includes heat-sensitive products like chocolate, gummies, and wax-based items. "FBA doesn't accept meltable inventory until October 16 or April 14."
Items from October 16 through April 14 are prohibited. Perishable goods requiring refrigeration or air conditioning are banned. Fulfillment centers maintain temperatures around 75-150 degrees Fahrenheit during summer. Amazon may charge premium storage fees for heat-sensitive products, particularly summers.
11. Restock Inventory
Restock inventory describes "the recommended replenishment amount that you should send Amazon FCs," specifying timing to maintain stock.
Amazon's FBA Restock Inventory tool considers sales history, demand forecasts, and seasonality, allowing adjustments for lead time, case pack quantity, and frequency. However, limitations exist:
- Amazon only considers total sales, not adjusted velocity
- Algorithm ignores separate supplier/3PL lead times
- Doesn't account for warehouse or supplier inventory
Relying solely on Amazon risks over or under-ordering. With recent ASIN-level restock limits and capacity controls, robust inventory management tools integrating predictive analytics and real-time data prove essential.
12. Amazon Inventory Missing or Lost
Lost inventory occurs through shipping errors like misrouted trailers. "A 3PL owner was involved in an incident in which a trailer was supposed to be taken to Nevada, but instead went to California."
Location mistakes affect delivery times. Finding lost packages may take weeks or months. Amazon typically requires waiting 3-7 days before declaring inventory lost.
Amazon reimburses lost inventory costs based on recent selling prices. Lost inventory may not receive full reimbursement if product prices dropped. If items resurface, Amazon returns them to the seller's account for resale.
Tip 1: Document trailer numbers and Bills of Lading for tracking lost shipments.
Tip 2: Work with service providers offering automatic missing stock ticket support or manual documentation assistance. SPACEGOATS checks automatically monthly.