Inventory Valuation Methods for SMEs

The main inventory cost formulas relevant to many SMEs are specific identification, first-in first-out and weighted average. IFRS IAS 2 states that specific identification is used for inventory items that are not ordinarily interchangeable, while FIFO or weighted average is used for ordinarily interchangeable items. The correct policy depends on the applicable reporting requirements and business facts; it should be selected and documented by qualified finance advisers.

This operational guide does not provide accounting or tax advice. Use the inventory systems service to align the selected policy with item, receipt and fulfilment data. Pair it with damaged-stock controls and the stock-count guide.

What IAS 2 establishes

IAS 2 describes inventories as measured at the lower of cost and net realisable value. Cost includes purchase, conversion and other costs incurred in bringing inventory to its present location and condition. Net realisable value is the expected ordinary-course selling price less estimated completion and selling costs. The standard also addresses recognising write-downs and inventory losses as expenses. Finance must apply those principles to the actual entity, items and evidence.

1. Do not confuse cost formula with physical picking

FIFO as an accounting cost formula and FIFO as a warehouse removal rule are related concepts but not automatically the same system function. A warehouse may physically pick by expiry or location while finance assigns costs under its policy. Document both. If lot or serial tracking is required to connect a unique item to cost, test that link through receipt, transfer, sale and return.

2. Define the inventory cost components

List which purchase price, freight, duty, handling, conversion labour, production overhead and other costs are included under the policy. Decide how supplier discounts, rebates, foreign currency, landed-cost allocations and purchase price changes enter item cost. A spreadsheet posted at month end can create a value that operations cannot trace back to items or receipts; design the allocation evidence before automating the journal.

3. Stabilise quantity and unit data

A correct unit cost applied to a wrong quantity still produces a wrong valuation. Set one base inventory unit for each item and controlled purchase, production and sales conversions. Reconcile negative stock, backdated transactions, unposted receipts, returns, transfers and count adjustments before evaluating the costing method. Prevent users from changing a base conversion after transactions exist without a governed migration.

4. Understand weighted-average configuration

Microsoft Business Central documents average cost as a periodic weighted average and allows an average cost period plus a calculation type such as item or item by variant and location. That illustrates why the phrase ‘average cost’ is not enough: the period and level of calculation affect the result. Confirm the software configuration against finance policy and test purchases at different prices, partial sales, returns and late invoices.

5. Protect cut-off and cost adjustment

• Record goods received in the correct period even when the supplier invoice arrives later.
• Resolve receipts without cost, invoices without receipt and returns awaiting credit.
• Control backdating after the inventory period is reviewed or closed.
• Run the system cost-adjustment process required by the platform.
• Reconcile inventory value before and after late-cost adjustments.
• Keep a review of negative inventory and transactions posted out of sequence.

6. Test write-downs and recoverable value separately

A cost formula assigns cost; it does not decide whether recorded inventory value remains recoverable. Identify damaged, obsolete, expired and slow-moving items through operational evidence. Finance should review estimated selling price, completion and selling costs where relevant. Keep the quantity movement, condition decision and valuation entry linked without assuming every slow-moving unit has zero value.

7. Reconcile the subledger to the general ledger

Worked comparison

An equipment dealer holds individually serialised high-value machines and interchangeable spare parts. Finance determines that the machines require specific identification while the parts use FIFO under its reporting policy. The pilot receives two machines with different landed costs, transfers one, sells and returns it, and verifies the serial-specific cost. It also purchases one part at two prices, sells a partial quantity and tests the FIFO issue layers. Damaged parts are quarantined and reviewed separately for recoverable value.

Implementation acceptance test

Use opening stock, two purchase prices, freight allocation, partial receipts, a return, transfer, count adjustment, damaged item, sale and refund. Close the period and reconcile quantity, inventory value, cost of sales and the control account. Repeat after a late supplier invoice. The configuration passes only when finance can reproduce the result and operations can trace every quantity and cost event.

Sources checked

• IFRS Foundation: IAS 2 Inventories
• Microsoft Learn: Average cost design details
• Microsoft Learn: Costing method setup best practices

This resource provides general implementation guidance. Verify platform settings, tax, legal, payment and operational requirements against the current business context before making a live change.