Why Inventory Accounting Actually Matters
For most of the UK FBA businesses we work with, inventory is the single largest asset on the balance sheet. Treat it as an afterthought and your accounts misstate the value of the business and your taxable profit. HMRC requires inventory to be valued at the lower of cost or net realisable value, which sounds simple until you remember that FBA inbound shipping, prep services, storage fees and dimensional weight all feed into the real unit cost.
What Goes Into Cost of Goods Sold
Cost of goods sold is the direct cost of the products you actually sold in the period. For FBA, that includes the supplier invoice cost, inbound freight, customs duty, supplier prep or labelling fees, and any costs incurred before the product became sellable on Amazon. The treatment of ongoing FBA fees and advertising spend varies between practitioners. What matters most is consistency in how you categorise costs year to year, and clarity on what is sitting in COGS versus operating expenses so your gross margin reflects reality.
Tracking Stock as It Moves Through FBA
Stock comes in as inbound shipments and leaves as customer orders, returns, removals or disposals. Each of those needs to be reflected in the accounts. Spreadsheet-based approaches start to break down once you sell more than a few SKUs. Specialist tools like A2X, SellerBoard or Link My Books pull this data in, map it correctly, and post monthly accounts that reflect what actually happened in Amazon’s warehouse.
Returns and Damaged Stock Need Different Treatment
Amazon returns are not one thing. Some come back sellable and go back into your inventory. Some come back damaged and become unsellable. Some never come back at all. Each scenario has a different accounting treatment. Resold returns keep their full cost in inventory. Damaged stock written off becomes an expense. Lost stock that Amazon reimburses you for becomes income. Treat all returns the same way and you will misstate inventory, expenses and revenue at the same time.
Year-End Stock Valuation: Where People Get Burned
At year end you need a clean count of stock at FBA warehouses valued at cost. Amazon gives you the units. It does not give you the cost basis. You apply weighted average or first-in-first-out costing to turn units into a pound figure. Get this wrong by a few thousand pounds in either direction and your taxable profit moves by the same amount. We have seen this swing a corporation tax bill by four-figure sums without anyone noticing until the accounts are signed.
Getting Amazon Accounting Right
A specialist Amazon accountant sets up your inventory accounting properly from day one, integrates it with your accounting software, and keeps it accurate month after month. The result is that you always know your real margin and your real tax position, which is the foundation of every other decision you make about the business.
Stop manually reconciling payouts and worrying about hidden VAT errors. Book a free consultation with our team. We will set up your automated connectors, clean up your Xero chart of accounts, and manage your monthly compliance so you can focus entirely on growing your store.
