Three-Way Inventory Reconciliation: 3PL Receipts, the Amazon Ledger and the ERP

By Bernardo Campelo, Forbes Business Council E-Commerce Leader, Amazon SPN Certified provider, Amazon SP-API authorized partner, and Founder of PrepVia.

Picture the third business day of a month-end close. A brand's controller has one SKU and three numbers on her screen. The 3PL says it received 4,787 units in August. Amazon's Inventory Ledger says 3,618 units sit in fulfillment centers. The ERP says the company owns 5,515. Her question fits in one line: which system is wrong?

Usually none of them. Each number answers a different question, at a different moment, in a different unit. The 3PL counts what crossed its dock. Amazon records what its scanners touched. The ERP holds whatever somebody posted, at a cost.

Three-way reconciliation is not a hunt for the right number. It is a monthly routine that gives every unit of difference one of five labels: timing, unit of measure, adjustment, loss or removal. Only the unexplained residue goes to a claim, a supplier or your accountant.

Three Records, Three Different Questions

Counting is not one event. In a July 20, 2026 DC Velocity piece, Ben Ames described counts at the vendor, the receiving dock, the racks, and every pick, pack and ship. Each is a point where a discrepancy can start. The hard part is aligning them with a system of record such as a WMS or an ERP.

An Amazon brand lives that problem across three companies, and the ERP holds a fourth version, usually a few days late.

On September 24, 2026, Amazon announced end-to-end supply chain visibility rolling out over the coming weeks: one interface tracking a shipment from creation across Amazon-managed fulfillment, with a single reconciled unit count. Note the scope. Your 3PL's dock is not Amazon-managed, and your ERP never will be. Amazon has not published how the new count works, so nothing below depends on it.

The Amazon Reports That Feed the Close

For reading one shipment's receipts line by line, start with how the Amazon Inventory Ledger works. These are the reports to pull, named as they appear in Amazon's FBA report type documentation.

• Ledger Summary View (GET_LEDGER_SUMMARY_VIEW_DATA). Amazon compares it to a bank statement for your inventory. It aggregates by country or fulfillment center, and by day, week or month. Columns include StartingWarehouseBalance, InTransitBetweenWarehouses, Receipts, CustomerShipments, CustomerReturns, VendorReturns, Found, Lost, Damaged, Disposed, OtherEvents, UnknownEvents and EndingWarehouseBalance. A monthly API pull must run from the first to the last day, or it can return empty data.
• Ledger Detail View (GET_LEDGER_DETAIL_VIEW_DATA). Eighteen months of movements, filterable by event type and by FNSKU, MSKU or ASIN, with ReferenceID, FulfillmentCenter, Disposition and Reason. It also carries ReconciledQuantity and UnreconciledQuantity. Amazon's Inventory Ledger help page defines them for misplaced, found and fulfillment-center-damaged rows: as an adjustment is reconciled or reimbursed, unreconciled falls and reconciled rises.
• Removal Order Detail and Removal Shipment Detail. The first helps reconcile units requested against units actually removed. The second gives carrier, tracking and shipped quantity.
• Reimbursements (GET_FBA_REIMBURSEMENTS_DATA). Updated daily, with the reason for each line and separate quantities reimbursed in cash and in inventory.
• AWD. The ledger is described as covering movements to and from Amazon fulfillment centers. The AWD API is a separate source for inventory inside AWD and units in transit to AWD or from AWD to FBA. Amazon's separate AWD Inventory Ledger report counts boxes, with a Package Quantity field, not units.

Two warnings for whoever maintains your ERP connector, from Amazon's SP-API deprecation schedule. GET_FBA_RECONCILIATION_REPORT_DATA, GET_FBA_FULFILLMENT_INVENTORY_RECEIPTS_DATA and GET_FBA_FULFILLMENT_INVENTORY_ADJUSTMENTS_DATA were removed on January 31, 2023, so a template that still names them points at nothing. And GET_V2_SETTLEMENT_REPORT_DATA_FLAT_FILE and GET_V2_SETTLEMENT_REPORT_DATA_XML are removed on November 11, 2026, with the Finances API v0 operations listFinancialEvents, listFinancialEventsByGroupId and listFinancialEventsByOrderId following on August 27, 2027. Ask your vendor, in writing, what it reads after each date.

Five Reasons the Three Numbers Disagree

In my experience, almost every gap lands in one of five buckets. Each one clears differently, and only loss is inventory that is actually gone.

Timing

Your 3PL ships on the 28th, Amazon's receipts post in waves, and the month ends on the 31st. That shipment is not a variance. It is a pipe: units between custodians. Give each open shipment a line with its ship date and let it age. Amazon says reconciliation of shipped inventory usually takes 2 to 30 days, and in some cases up to 60. Do not file on a pipe. Under the shipment to Amazon claims policy, you file once the shipment shows as eligible for investigation, within nine months of verified delivery, and only one claim per shipment is accepted. The FBA inventory reimbursement policy also warns that repeated premature requests can delay support on your cases.

Unit of measure

Your supplier invoices cases. Your 3PL counts eaches inside cartons, and the gap between a real count and a said-to-contain count is covered in how your cartons get received. Amazon counts FNSKU units, so a three-pack under one FNSKU is one unit to Amazon and three to an ERP tracking components. If you buy in case packs and sell in units, expect this bucket to be busy on your first close.

Adjustment

Found, Lost, Damaged and Disposed are separate Summary View columns, and each Detail View row carries a Reason. Your 3PL has its own: dock damage, recounts, units scrapped in prep. A Lost row can be answered by a Found row weeks later, even on another SKU when a unit was mislabeled, and a replacement unit comes back as Inventory found. Amazon also says it can reverse a reimbursement if the item is later found and returned to your inventory. Track the pair, not the half.

Loss

Where custody sat when units went missing decides the path. Short supplier cartons are a supplier conversation, backed by your 3PL's signed discrepancy. An inbound shortfall goes through the shipment claim, where Amazon asks for proof of ownership with purchase date, product names and quantity, plus a POD stamped by Amazon with box count and weight for LTL or truckload, or tracking IDs for small parcel. Units lost inside a fulfillment center have a 60-day claim window from the day they are reported lost or damaged.

Two eligibility rules sit upstream: you must have sent the exact items and quantities in your shipping plan, and shipments created after January 1, 2026 that arrive without proper prep and labeling are not eligible if damaged or untraceable, per the FBA Prep Service page. Both are settled at your 3PL's packing table. If a claim still comes back denied, read the common denial patterns before you appeal.

Removal

When your return address is your 3PL, removals are counted on its dock, and the removals claims policy runs short clocks. Lost in transit: no sooner than 15 days after the last confirmed movement and within 75 days of creation. Damaged: within 60 days of delivery. For a short or damaged removal, Amazon asks for images of the units, tracking labels or packing slips, and damaged boxes, a POD that calls out the short receipt, and the packing list marked. The operating side is in our removal orders guide.

What Your 3PL Has to Hand You Each Month

The 3PL record is the only one of the three you can shape by contract. Ask for this packet by name.

None of this guarantees a claim: Amazon decides claims, and no 3PL record binds it. The packet makes sure your side of the file exists before a clock runs out. At PrepVia in Miami we count every carton against the packing list and the BOL and report discrepancies with photos within 24 hours of arrival. This is still the list I would hand any brand evaluating any 3PL, us included.

The Reconciliation Workbook: Columns and Tolerance Rules

This is the instrument: one row per FNSKU, one tab per month.

Expected units equal 3PL closing plus inbound pipe plus Amazon balance plus removal pipe plus AWD. The Amazon balance is Ending warehouse balance plus In transit between warehouses, summed across dispositions, per Amazon's ledger conversion guide. Variance is ERP units minus expected. Apply these rules in order.

A Worked Month: Where the Cost Layer Breaks the Tie

Back to the controller's SKU, with every number illustrative. It ships in cases of 24. Last month closed clean: 600 units at the 3PL, 3,100 at Amazon, empty pipes, 3,700 in the ERP.

• 3PL. The supplier invoiced 200 cases, 4,800 units. The 3PL counted 199 full cases and one open case holding 11, so 4,787, and signed a 13-unit discrepancy. It shipped two FBA shipments of 2,400 units each and logged 6 units crushed at the dock. Closing: 581.
• Amazon. Summary View, all dispositions, none in transit between warehouses: 3,100 starting, 3,550 received, 3,020 shipped to customers, 35 returned, 40 removed, 12 lost, 5 found. Ending: 3,618. The second shipment shows 1,150 of 2,400 received, still posting.
• Pipes. Inbound: 1,250. Removal: 40 units shipped on the 26th, not yet counted at the 3PL.
• ERP. Receipt booked from the invoice at 4,800, sales and returns from the settlement feed, no adjustments posted. Units: 5,515.

Expected: 581 plus 1,250 plus 3,618 plus 40, or 5,489. Variance: 26, which does not map to whole cases. The 13-unit supplier short is a loss with a signed discrepancy behind it. The 6 crushed units are a 3PL adjustment your contract assigns. Amazon's 12 lost against 5 found leaves 7 unreconciled, with a 60-day clock. Residue: zero. The 1,250 and the 40 are pipe.

Now change one fact. If the ERP had posted the receipt as 200 because the PO line was in cases, the variance would swing by 4,600 units: 200 cases each missing 23. A number that tidy is master data, not a warehouse problem.

Then the cost layer. Say the ERP carries this SKU at a landed cost of $6.40 and the sourcing cost you entered on Manage Your Sourcing Cost is $4.10, both illustrative. Before fulfillment, Amazon reimburses sourcing cost, which excludes shipping, handling and customs duties, or its own estimate if you entered none. Paid in cash, the 7 missing units leave a $2.30 gap per unit that will not close on its own. Build that number from a fully loaded landed cost.

The Five-Day Close

The first close takes longer, because the unit-of-measure bucket is full of master data nobody fixed. If you are a brand weighing where a 3PL fits in this, see how we work with brands.

Frequently Asked Questions

What is three-way inventory reconciliation for an Amazon brand?

It is a monthly tie-out between three records of the same inventory: your 3PL's receiving and on-hand record, Amazon's Inventory Ledger, and the units and cost in your ERP. The goal is to give every unit of difference a cause and act only on what stays unexplained.

Which Amazon report should I use for the monthly inventory close?

Use the Inventory Ledger Summary View for the calendar month, plus In transit between warehouses, as the Amazon balance. Use the Detail View, which holds 18 months of movements, to match receipts to FBA shipment IDs and trace adjustments. Add the two removal reports and the Reimbursements report, and pull AWD from its own ledger.

Why does my ERP show more units than my 3PL and Amazon combined?

Common causes are receipts booked from the supplier invoice instead of the 3PL count, adjustments nobody posted, and units in transit that neither custodian shows yet. Build the inbound and removal pipes first. Then compare posted receipts to the signed receiving count.

How much does Amazon pay when it reimburses a lost FBA unit?

For shipment, removal and fulfillment center claims before fulfillment, Amazon reimburses the sourcing cost you entered on Manage Your Sourcing Cost, or its own estimate if you entered none. Sourcing cost excludes shipping, handling, customs duties and other costs. The maximum for a single unit is $5,000, and Amazon may replace the unit instead of paying cash.

What should my 3PL send when it finds a receiving discrepancy?

A count per carton against the expected quantity, a discrepancy report signed and dated by the receiver, photos of short, open or damaged cartons, and any exception noted on the carrier delivery receipt. That record supports your supplier conversation and your claim file, but it does not bind Amazon.

Will Amazon's new single reconciled unit count replace this work?

Not as announced. On September 24, 2026 Amazon said the count covers Amazon-managed fulfillment, and it has not published how the count works. Your 3PL dock and your ERP cost layer sit outside that scope, so the three-way close stays yours.

Final Take

Three records will never show the same number, and they should not. The 3PL counts a dock, Amazon counts a network, and the ERP counts money. The close is where the three stories become one.

The method is short: Summary View for the month, Detail View for tracing, pipes and AWD on their own lines, and a label on every unit of variance before anybody calls it missing.

The piece you control most is the 3PL record. Per-carton receipts, signed discrepancies, photos and dates turn a claim clock from a threat into a calendar entry. Put them in the contract, then ask for them every month.