The single most common bookkeeping error in manufacturing businesses is the incorrect treatment of production costs as period expenses. Expensing direct materials, direct labour, and manufacturing overhead through the P&L rather than capitalising them into inventory understates the balance sheet and overstates expenses in production-heavy periods — distorting both the income statement and the stock position.
COGS vs. Period Costs: The Fundamental Split
Product costs — those that attach to the goods being manufactured — must flow through inventory before hitting the P&L as cost of goods sold. This category includes direct materials (raw materials and components consumed in production), direct labour (wages of workers who physically transform the product), and manufacturing overhead (factory rent, utilities, depreciation on plant, production supervisors' wages).
Period costs — selling, administrative, and finance costs — do not attach to the product and are expensed in the period incurred. Common misclassifications include factory manager salaries (product cost), sales team wages (period cost), and general accounting fees (period cost). The distinction matters because a manufacturing business that classifies its factory overhead as a period cost will show erratic margins tied to production volume rather than a stable gross margin reflecting the true cost of output.
WIP Valuation Under AASB 102
At each reporting date, goods that have been started but not completed must be valued and carried on the balance sheet as work-in-progress inventory. AASB 102 Inventories requires WIP to be measured at the lower of cost and net realisable value. Cost for WIP means the proportion of raw materials consumed, direct labour hours applied, and manufacturing overhead absorbed — calculated at the stage of completion of each batch or job.
The practical method most small manufacturers use is a standard cost system: each product has a standard cost card that specifies material, labour, and overhead per unit. WIP is valued by multiplying the percentage of completion by the standard cost. The bookkeeper's job at period end is to capture the physical count of WIP units, their stage of completion, and apply the standard cost. Significant variances between standard and actual cost should be investigated — they often indicate process inefficiency or costing errors.
BOM Reconciliation and Variance Analysis
Most manufacturing software (MYOB Advanced, Cin7, or purpose-built ERP systems) maintains a Bill of Materials that specifies the quantity of each input required to produce one unit of output. At period end, the bookkeeper should reconcile actual input consumption (from purchasing and inventory records) against the BOM-expected consumption for the actual output produced. The difference is the usage variance.
An adverse materials variance (more materials consumed than the BOM predicts) may indicate waste, scrap, theft, or an out-of-date BOM. A favourable variance can indicate the BOM is overstated or that a different grade of material is being substituted. Either way, unexplained variances warrant investigation before the financial statements are finalised. Systematic BOM reconciliation is also a critical internal control — it is one of the few mechanisms that can detect raw material theft at the production floor level.
Instant Asset Write-Off for Manufacturing Plant
Under the temporary full expensing rules (and the ongoing small business instant asset write-off), eligible depreciating assets acquired for a manufacturing business may be immediately deducted in the year of acquisition. Manufacturing plant — lathes, welding equipment, CNC machines, conveyor systems — qualifies as plant under Div. 40 ITAA 1997.
Two restrictions apply that are particularly relevant to manufacturers. First, second-hand assets acquired from a connected entity or affiliate are not eligible for temporary full expensing (though they may still qualify under the standard instant asset write-off threshold for small businesses). Second, the asset must be used or installed ready for use before the end of the income year. Equipment that arrives on 28 June but is not unpacked and commissioned until August does not qualify in the earlier year. Bookkeepers should confirm commissioning dates with the client and not rely solely on invoice dates.
GST on Imported Raw Materials: The Deferred GST Scheme
Raw materials and components imported into Australia attract GST on the customs value (which includes the cost of goods plus insurance and freight — the CIF value — plus customs duty). Without the Deferred GST Scheme, GST is payable at the border before the goods are released by the Australian Border Force — a cash flow disadvantage for manufacturers who import large volumes regularly.
The Deferred GST Scheme (DGST), administered under s.33-15 of the GST Act, allows eligible importers to defer the GST on imports to their next BAS lodgement. To be eligible, the business must be GST-registered, have a good compliance history, and be approved by the ATO. Once approved, the importer pays the customs duty at the border but defers the GST — reporting it as both a GST liability (1A) and a corresponding ITC (1B) on the same BAS. The net cash effect is nil for fully creditable businesses, which is the point — it eliminates the working capital tie-up.
Customs duty itself is not subject to GST and is not an ITC-eligible cost. It is a cost of the inventory and is absorbed into the cost of goods manufactured.
Export Sales: Zero-Rating and Documentation Requirements
Finished goods exported from Australia are GST-free under s.38-185 of the GST Act. The zero-rating applies provided the exporter holds documented evidence that the goods were exported within 60 days of the earlier of the invoice date or the date of payment. Required documentation includes the export declaration lodged with the Australian Border Force, the bill of lading or airway bill, and evidence linking the export declaration to the specific invoice.
The bookkeeper must ensure that export invoices are coded as GST-free (the FRE code in most accounting systems) rather than as taxable supplies. Miscoding export sales as taxable will overstate the GST liability on the BAS. Conversely, if the goods are not actually exported within the 60-day window — for example, because the shipment is delayed — the supply becomes taxable and GST must be remitted even if the invoice was originally issued as GST-free. A tickler system tracking the 60-day deadline on each export invoice is a worthwhile internal control for high-volume exporters.