Amazon Inventory Ledger reason codes explained
The Reason column of the FBA Inventory Ledger holds short codes — M, F, E, P and a dozen more — that say why Amazon changed your stock. Here is what each one means, whether it is Amazon's fault, and what to do about it.
By Vedant Agarwal, who builds WidenMargin's toolsUpdated
Every reason code at a glance
| Code | What it means | Amazon's fault? | What to do |
|---|---|---|---|
| M | Missing from a bin location (lost) | Yes | Amazon reimburses most of these automatically. If it hasn't, claim within 60 days of the loss. |
| 5 | Missing from a bin location (lost) | Yes | Amazon reimburses most of these automatically. If it hasn't, claim within 60 days of the loss. |
| F | Missing inventory found | Cancels an earlier loss | Nothing — the unit is back. Subtract it from any earlier M or 5 for the same SKU. |
| N | Transferred in from an incorrectly assigned FNSKU | Cancels an earlier loss | Nothing — the unit is back. Subtract it from any earlier M or 5 for the same SKU. |
| E | Damaged at an Amazon fulfillment center | Yes | Amazon reimburses most of these automatically. If it hasn't, claim within 60 days. |
| 6 | Carrier-damaged | Sometimes | Review the event: carrier damage and disposals are only sometimes Amazon's responsibility. |
| D | Disposed of | Sometimes | Review the event: carrier damage and disposals are only sometimes Amazon's responsibility. |
| H | Customer-damaged | No | Nothing to claim — this is not a warehouse loss, or it is a bookkeeping move between conditions. |
| K | Defective | No | Nothing to claim — this is not a warehouse loss, or it is a bookkeeping move between conditions. |
| U | Distributor-damaged | No | Nothing to claim — this is not a warehouse loss, or it is a bookkeeping move between conditions. |
| 7 | Expired | No | Nothing to claim — this is not a warehouse loss, or it is a bookkeeping move between conditions. |
| Q | Disposition change (removed) | No | Nothing to claim — this is not a warehouse loss, or it is a bookkeeping move between conditions. |
| P | Disposition change (re-added) | No | Nothing to claim — this is not a warehouse loss, or it is a bookkeeping move between conditions. |
| 3 | Product redefinition — transfer in | No | Nothing to claim — this is not a warehouse loss, or it is a bookkeeping move between conditions. |
| 4 | Product redefinition — transfer out | No | Nothing to claim — this is not a warehouse loss, or it is a bookkeeping move between conditions. |
| O | Transferred out (mis-received or already reimbursed) | No | Nothing to claim — this is not a warehouse loss, or it is a bookkeeping move between conditions. |
Codes are Amazon's published adjustment codes. If your file shows a code not listed here, it is safest to treat it as unexplained and check the event in Seller Central before claiming anything.
Codes that come in pairs
A change of condition shows up as two rows: a removal (Q, E, 6, 7, H, K or U) and a matching P that adds the same unit back under its new condition. Count the removal once — adding both rows together makes a single damaged unit look like two events. Likewise an M or 5 (lost) followed later by an F or N for the same product means the unit was found: nothing is owed for it.
Check your own ledger
The lost & damaged inventory finder reads these codes from your Inventory Ledger in your browser, nets found units against losses, subtracts what Amazon already reimbursed, and shows any unit still inside the 60-day claim window. Refunds where the item never came back are a different report — see the refunded-but-not-returned finder.
For the other side of the check, see reimbursement report reasons explained and customer returns dispositions explained.
Questions about Inventory Ledger reason codes
Where do I find the reason codes?
In Seller Central go to Reports, then Fulfillment, then Inventory Ledger, and choose the Detailed view. Each row has an Event Type (Receipts, Shipments, Customer Returns, Adjustments and so on) and, on adjustments, a one- or two-character code in the Reason column. The Summary view does not show reason codes.
What does reason code M mean?
M means Amazon cannot find a unit in its bin location — the unit is treated as lost (misplaced). Code 5 means the same thing. If the unit turns up later, you will see an F (found) or N (transferred back from a wrong FNSKU) for the same product, which cancels the loss.
What does reason code E mean?
E means the unit was damaged inside an Amazon fulfillment center — Amazon's fault. It moves the unit out of your sellable stock; you will usually see a matching P code re-adding it under a damaged condition, so count the E once, not twice.
Why does every Q or E have a matching P?
Q, E, 6, 7, H, K and U remove a unit from one condition, and P adds it back under the new condition (for example from sellable to warehouse-damaged). The pair is a change of status, not two separate events, so only the removal side says what happened.
Does Amazon reimburse these automatically?
Since November 2024 Amazon reimburses most units it loses or damages in its fulfillment centers without a claim. Claims for the ones it misses must be filed within 60 days of the loss being reported (the window was 18 months before 23 October 2024). The lost & damaged inventory finder checks your ledger against your reimbursements report for exactly this.