Amazon FBA automatically distributes your inventory across multiple fulfillment centers based on demand patterns and shipping optimization. You don’t control which warehouses receive what quantity. Amazon decides, and the inventory moves between facilities without your input.

Seller Central provides the Inventory Ledger report which shows every unit movement including receiving, sales, transfers between warehouses, adjustments, and removals. This report is your primary source for understanding inventory flow. The FBA Inventory Age report and Inventory Health report add context about how long units have been sitting and storage fee exposure.

For accounting purposes, the physical warehouse location usually doesn’t matter for inventory valuation. Whether units sit in Phoenix or Pennsylvania, you value them the same using FIFO, weighted average, or your chosen method. What matters is that your total unit counts and dollar values match what Amazon reports across all locations combined.

The real challenge is reconciliation. Amazon constantly adjusts inventory for damaged goods, lost units, customer returns in various conditions, and warehouse discrepancies. If your books don’t capture these adjustments, your inventory valuation slowly drifts from reality. By year end, you might show inventory you don’t actually have or miss reimbursements you’re owed.

Integration software like A2X or Link My Books pulls Amazon transaction data directly into QuickBooks or Xero. These tools categorize sales, fees, refunds, and inventory adjustments automatically so you’re not manually entering thousands of transactions. They handle the complexity of Amazon’s settlement reports and translate them into proper accounting entries.

Run the FBA Inventory Reconciliation report monthly. Compare what you shipped to Amazon against what they received, what sold, and what’s still in stock. Amazon makes mistakes. Units disappear. You’re entitled to reimbursements for inventory they lose or damage, but you have to identify the discrepancies and file claims.

If you sell through multiple channels beyond Amazon, you need a system that consolidates inventory data. Selling the same product on Amazon, Shopify, and at a local retailer means tracking three separate inventory pools that all draw from your total stock. Software like Cin7 or Ordoro can sync inventory across platforms and feed into your accounting system.

A Scottsdale bookkeeper with e-commerce experience can help you set up these systems correctly from the start. Getting the integrations and reconciliation processes right early prevents the scramble of sorting out inventory discrepancies at tax time when the records are months old and details are forgotten.

The complexity scales with volume. Someone moving 50 units monthly can reconcile manually using Amazon reports and a spreadsheet. A seller moving thousands of units across FBA, merchant fulfilled, and wholesale channels needs proper inventory accounting systems and likely professional help to maintain accurate records and catch the money Amazon owes them.