"Every month the stock ledger and Seller Central disagree, and every month I write off the difference and move on. There is almost half a million pounds of our stock sitting in FBA. What is it actually costing us to keep losing a little of it every month?"
That is the right question, and it is why the month end that matters for an Amazon supplement brand is a stock reconciliation, not a settlement one. Here is the direct answer: reconcile the FBA Inventory Ledger to your stock account every month, match every lost or damaged unit to a reimbursement at sourcing cost, and file each claim inside its window before the door closes. In the illustrative month below, the work recovered £1,102.50 and exposed £249.50 of leaks that never appear on the dashboard.
Every figure below is an illustrative example with synthetic numbers, built to show the shape of the process. Your product mix, your windows and your sourcing costs will differ.
Here's the Short Version
- Supplements are a specific FBA problem: small runs, high unit values, expiry dates, and slow-moving SKUs where a lost unit can sit unnoticed for months
- Amazon reimburses most warehouse losses automatically now, but removal claims are still manual, and every claim runs on a window measured in days, not years
- Since 31 March 2025, losses before a customer order are reimbursed at your sourcing cost: what you paid the manufacturer, excluding freight and duty. That gap lands on you
- The current UK windows: warehouse loss or damage within 60 days of the report, customer returns between 45 and 105 days after the refund, removals on their own short clocks
- The month end in five steps: pull the reports, reconcile in units, match every adjustment to a reimbursement, file what is claimable, then book it
- In the illustrative month: £1,102.50 recovered, a £67.50 lapse, and £182 of landed cost that never comes back
Why Supplements on FBA Need Their Own Discipline
A supplement catalogue is wide and shallow: dozens of SKUs, each a batch with a best-before date, and several of them selling in single-digit units in a month. That shape is exactly where FBA losses hide. A missing unit on a fast seller gets noticed within a week; a missing unit on the third-best flavour of a greens powder can sit in an adjustment note for a year.
Three more things make supplements different. Unit values are high, so small unit counts carry real money; a £4.50 capsule bottle on the wrong end of an adjustment is cash, not noise. Expiry writes work differently from ordinary shrinkage: stock is removed or disposed of at your instruction, and if the removed units never land back in your stock ledger they become a mystery balance. And subscription orders and repeat purchases add return paths, including the refund that was never followed by a returned parcel.
The result is predictable: stock that exists on the balance sheet but not on a shelf, reimbursements that arrive without anyone noticing, and claims that quietly age out of their windows. None of it shows on the Seller Central dashboard, because the dashboard is built for selling, not for reconciling.
The Month End, Step by Step
The method we run for supplement brands takes the better part of a day once the process exists, and it lives in the accounts rather than in a spreadsheet bolted on the side. Five steps.
One, pull the reports. The FBA Inventory Ledger is the unit story: receipts, shipments to customers, customer returns, adjustments, removals and disposals, movement by movement. The Reimbursements report shows what Amazon has already paid you. The Inventory Adjustments report lists the losses by reason code, and the settlement reports keep the money side honest. Four downloads, one working file.
Two, reconcile in units, not pounds. Every negative adjustment either has a cause you own (damage in your own inbound packing, expiry, a removal you requested) or one Amazon owns (warehouse damage, loss in transit between fulfilment centres, units that never made it out of an inbound shipment). Amazon-owned causes are potential reimbursements. Work in units first, because units are facts; the pounds follow from the unit cost.
Three, match every adjustment against the Reimbursements report. Since early 2025 Amazon proactively reimburses most warehouse losses and damages, so plenty of events settle themselves. The discipline is confirming that each one did: adjustment found, reimbursement matched, and any difference either claimed or written off on purpose. Do not double-file. A manual claim on an event Amazon has already paid gets denied and can pull your account into review.
Four, file what is claimable, immediately. Anything Amazon-owned and unpaid becomes a claim, and the clock started the day the event was reported. Removal claims are always manual, so they need their own calendar entry. If a reimbursement comes in below your true cost, there is a valuation appeal window of 60 days from the payment.
Five, book it. Lost stock is written off at cost; the reimbursement is a credit that lands against it. Closing stock on the balance sheet is the reconciled closing units at your unit cost, and the accounts and the ledger now tell one story. The detailed double entry is in our guide to accounting for FBA reimbursements.
Illustrative Example: One Month at a £2m Supplement Brand
Here is a single month's stock movement for an illustrative £2m supplement brand selling on Amazon UK. Landed cost per unit is £5.20, of which £4.50 is the sourcing cost; the rest is freight and duty. Every figure is synthetic and rounded.
| Stock movement | Units | £ per unit | £ value |
|---|---|---|---|
| Opening FBA stock | 22,000 | £5.20 | £114,400 |
| Received from the factory | +10,000 | £5.20 | £52,000 |
| Shipped to customers | -8,300 | £5.20 | (£43,160) |
| Customer returns, back to sellable stock | +520 | £5.20 | £2,704 |
| Customer returns, unsellable | -90 | £5.20 | (£468) |
| Refunded but never returned by the customer | -10 | £5.20 | (£52) |
| Removed for expiry or aged stock | -900 | £5.20 | (£4,680) |
| Lost or damaged inside Amazon's network | -260 | £5.20 | (£1,352) |
| Closing FBA stock | 22,960 | £5.20 | £119,392 |
Read the bottom two lines first, because that is where the money is. Of the 260 units lost or damaged, Amazon auto-reimbursed 200 at the £4.50 sourcing cost: £900 that arrived without anyone filing anything. The next 45 units became a manual claim, filed the same week: £202.50. The last 15 units were reported 71 days before this run. Past 60 days, the window is closed, and £67.50 of stock is simply gone. Meanwhile, on all 260 reimbursed units the £0.70 of freight and duty per unit never comes back, because the sourcing cost basis excludes it: £182 of landed cost that no claim can recover.
So the month's reconciliation recovered £1,102.50 and surfaced £249.50 of permanent leaks, and it proved the closing stock number that goes on the balance sheet: 22,960 units at £5.20. Nothing about that month was dramatic. That is the point. The money is made in the version of this process that repeats every month before the windows close.
The Windows Are the Whole Game
Amazon shortened the reimbursement claim windows at the end of 2024 and the start of 2025, from 18 months to a matter of days for most claim types. The current UK settlement, as published in Seller Central, runs on three main clocks:
- A fulfilment centre operations claim, for stock lost or damaged in the warehouse, must be filed no later than 60 days after the item was reported lost or damaged
- A customer returns claim, where the refund went out and the item never came back, can be filed between 45 and 105 days after the refund or replacement date
- Removal claims run on their own short windows, from 15 to 75 days depending on the claim, and they are always filed manually
There is also a 60-day valuation appeal if a reimbursement lands below your true cost, and inbound shipment claims run on their own separate timeline. Two operational consequences follow. First, reconciliation can no longer be annual, or quarterly, or whenever someone remembers: a monthly close at minimum, and a weekly sweep of the adjustments report for high-value catalogues. Second, keep your sourcing cost current in Seller Central. Amazon estimates it where you have not told it otherwise, and since the March 2025 change that estimated figure is what it pays you; an out-of-date sourcing cost quietly shrinks every future reimbursement. If an item is later found in the warehouse, the reimbursement can be reversed, so the reconciliation has to be a living process, not a once-a-year project.
One note on reading your numbers: these claims are a stock matter, but they arrive as settlement lines, which is why the reconciliation and the settlement reconciliation at scale have to sit side by side. The stock side proves what was lost; the settlement side proves what was paid.
What Lands in the Accounts
The accounting itself is calmer than the chasing. Lost or damaged stock is written off at landed cost, and the reimbursement is recognised as a credit against that loss, as compensation rather than sales; it is not consideration for a supply, so it does not create output VAT, and the input VAT you reclaimed on the original purchase is unaffected. The one number that never comes back is the freight and duty gap, which is why importing brands should model landed cost and sourcing cost as two different figures, as we set out in the landed cost model for supplement brands. Keep the write-off, the adjustment note and the reimbursement credit linked in one audit trail, so both halves of the story are provable when HMRC or your buyer asks.
The Bottom Line
An Amazon supplement brand cannot treat FBA stock as a set-and-forget balance any more. The windows are short, the reimbursement basis is your sourcing cost, and the only way to keep the numbers true is to reconcile the units every single month. The illustrative month here recovered £1,102.50 and proved a closing stock figure of £119,392; the same month run late, or run once a year, recovers a fraction of that and quietly writes the rest off. General information, not financial advice; model your own numbers before you file.
If you sell supplements on Amazon and want this worked into your month end properly, that is exactly the work our Amazon supplement specialists run every month, reconciliation by reconciliation. Book a call and bring your last few months of Inventory Ledgers.