A stock auditor at an auto-component manufacturer in Chakan found Rs 18 lakh of unrecorded scrap across three production lines during a bank-mandated stock audit. The scrap - steel off-cuts, rejected castings, and machining chips - had accumulated over 14 months in the scrap yard. It was physically present, clearly visible, but completely absent from the stock register and the bank stock statement. The company had been reporting inventory values that did not account for the scrap generation, inflating both the book stock and the drawing power computed by the bank.
Manufacturing stock audit is fundamentally different from trading or retail stock audit. In trading, you count boxes on shelves. In manufacturing, you count raw materials in bins, half-finished components on production lines, finished goods in warehouses, and scrap in the yard - each requiring a different verification approach, a different valuation method, and a different set of documents.
This guide covers how stock audits work specifically for manufacturing companies - with separate sections for raw materials, WIP, finished goods, scrap, and stores/spares - including the verification approach, valuation rules, common findings, and the documents needed for each category.
Why Manufacturing Stock Audit Is Different from Trading
| Feature | Trading/Retail Stock Audit | Manufacturing Stock Audit |
|---|---|---|
| Inventory types | Finished goods only (purchased for resale) | Raw materials + WIP + Finished goods + Stores/Spares + Scrap |
| Valuation complexity | Purchase cost (straightforward) | Purchase cost (RM) + conversion cost (WIP/FG) including overhead allocation |
| Physical verification | Count items on shelves/racks | Count RM in bins, WIP on production lines, FG in warehouse, scrap in yard |
| Production records required | No | Yes - BOM, production orders, job cards, yield reports, scrap registers |
| Scrap/wastage verification | Minimal | Critical - scrap = RM cost minus FG output; yield analysis essential |
| Multi-stage inventory | No - goods are in one state | Yes - same material exists in RM, then WIP (multiple stages), then FG |
| Cutoff complexity | Low - receive or sell | High - must freeze production during count or apply rigorous cutoff procedures |
| Third-party stock | Rare | Common - job workers, surface treatment, heat treatment, testing labs |
Manufacturing companies in Pune, Mumbai, Chennai, and Bengaluru requiring CA-led stock audit services benefit from teams experienced in multi-category inventory verification, BOM-based reconciliation, and production-integrated counting - not generic counting services.
Key Terms
- Bill of Materials (BOM): The recipe for manufacturing - lists every raw material and quantity needed to produce one unit of finished goods. BOM is the foundation for yield analysis and scrap computation during stock audit.
- Conversion Cost: The cost of converting raw materials into finished goods - includes direct labour and allocated manufacturing overhead (both fixed and variable). WIP and FG cost includes conversion cost.
- Normal Capacity: The average production volume expected under normal conditions (Ind AS 2). Fixed manufacturing overhead is allocated to WIP/FG based on normal capacity - not actual capacity. Under-absorption of overhead when actual production is below normal is expensed, not added to inventory.
- Yield / Scrap Rate: The percentage of raw material that becomes finished goods (yield) vs the percentage that becomes scrap/waste. Standard yield is per BOM; actual yield is per production records. The difference is the variance to investigate.
- Cutoff Analysis: Ensuring that inventory movements (receipts, issues, transfers) during the physical count are properly controlled - no double-counting of items in transit between stages.
Who Needs a Manufacturing Stock Audit?
- Auto-component manufacturers - high-value steel/aluminium, multi-stage WIP, significant scrap (Chakan, Talegaon, Pimpri-Chinchwad, Manesar, Sriperumbudur)
- Pharma manufacturers - batch-tracked API and excipients with expiry dates, quarantine stock, temperature-controlled storage (MIDC Bhosari, Genome Valley)
- Chemical and process manufacturers - bulk liquids and solids requiring volumetric measurement, hazardous materials with special storage
- Food and beverage manufacturers - perishable raw materials, FEFO tracking, regulatory shelf-life compliance
- Electronics and appliance manufacturers - component-level inventory with thousands of SKUs, rapid obsolescence
- Textile manufacturers - fabric in different stages (greige, dyed, finished), significant size of WIP at dyeing/processing
- All manufacturers with CC/OD bank facilities - stock audit mandatory for borrowers above Rs 5 crore credit exposure
Manufacturers in Pune with dedicated stock audit in Pune teams can schedule on-site audits coordinated with production schedules - minimising disruption while ensuring complete coverage of RM, WIP, FG, and scrap.
Raw Material (RM) Audit: What the Auditor Checks
| Check Area | What the Auditor Does | Common Findings |
|---|---|---|
| Physical count | Count RM in bins, racks, open yards - by item code, batch (if batch-tracked), and location | Shortage due to unrecorded consumption; excess due to GRN not posted; items in wrong bin location |
| GRN reconciliation | Verify GRNs (Goods Received Notes) against purchase invoices and physical receipt | GRN posted but material not yet received (in transit); material received but GRN not posted |
| Ageing analysis | Identify RM not consumed for 6+ months | Slow-moving RM due to product design change; obsolete RM for discontinued products |
| Condition assessment | Check for damage, expiry, contamination, corrosion | Rusted steel stored in open; expired chemicals; water-damaged packaging |
| Valuation | Verify cost per unit using FIFO or weighted average; check against purchase invoices | Cost includes duties but ITC not adjusted (ICDS issue); inconsistent method across RM types |
| Third-party stock | Verify RM sent to job workers (heat treatment, surface coating, testing) with confirmations | RM at job worker not recorded in stock register; job worker confirmation not obtained |
Work-in-Process (WIP) Audit: The Most Complex Category
WIP is the most challenging inventory category to audit because it exists at multiple production stages, each with different degrees of completion. The auditor must verify both the physical quantity and the stage of completion to value WIP correctly.
| Check Area | What the Auditor Does | Common Findings |
|---|---|---|
| Stage identification | Identify WIP at each production stage - cutting, machining, assembly, finishing, QC | WIP between stages not tracked; production order not updated when material moves to next stage |
| Quantity verification | Count WIP units at each stage; verify against production orders and job cards | WIP quantity on production line does not match ERP; rejected WIP not segregated from good WIP |
| Completion % assessment | Determine the percentage of completion for valuation - materials 100% added at start vs progressively | Completion % not documented; auditor must rely on production manager estimate (audit risk) |
| Conversion cost allocation | Verify that WIP includes: RM cost + proportionate direct labour + proportionate manufacturing overhead | Overhead not allocated to WIP; WIP valued at RM cost only (under-valued); abnormal waste included in WIP cost |
| Normal capacity check | Verify that fixed overhead is allocated based on normal capacity, not actual capacity | Actual production below normal capacity but full overhead loaded to WIP (over-valued) |
| Rejection and rework | Identify rejected WIP; verify disposition (rework, scrap, or return to RM) | Rejected WIP counted as good WIP; rework cost not tracked; quality holds not segregated |
WIP Valuation Formula: WIP Cost = RM consumed (per BOM x units in process) + Direct Labour (hours x rate x completion %) + Fixed Overhead (allocated at normal capacity rate x completion %) + Variable Overhead (actual rate x completion %). Under Ind AS 2, abnormal waste, idle time, and storage costs (unless between production stages) are excluded from WIP cost and expensed immediately.
Finished Goods (FG) Audit
| Check Area | What the Auditor Does | Common Findings |
|---|---|---|
| Physical count | Count FG in warehouse/godown by product code, batch, and location | FG dispatched but delivery challan not posted; FG returned by customer but not recorded |
| Dispatch cutoff | Verify that goods dispatched near the audit date are correctly recorded - either in stock or in sales | Revenue recognised but goods still in warehouse; goods dispatched but invoice not raised |
| NRV assessment | Assess whether selling price minus selling costs exceeds cost; especially for slow-moving FG | FG with no orders for 6+ months; FG made to customer specification but order cancelled; aged FG requiring discount to sell |
| Valuation | FG cost = RM + conversion cost (full) per BOM x standard or actual cost | Cost per unit inconsistent; overhead allocation basis changed mid-year; scrap credit not adjusted |
| Packing materials | Verify packing materials as a separate category; check for adequate stock | Packing materials not included in FG cost; shortage of packing delaying dispatch |
Scrap and Rejection Audit
Scrap verification is where manufacturing stock audits find the most hidden value. Scrap is generated at every production stage - and if not systematically recorded, it accumulates unnoticed.
| Check Area | What the Auditor Does | Common Findings |
|---|---|---|
| Physical scrap count | Count/weigh scrap in the scrap yard by type (steel, aluminium, plastic, chemical waste) | Unrecorded scrap accumulation (months of production scrap not in register) |
| Yield analysis | Compare actual yield (FG output / RM input) against BOM standard yield | Actual yield 2-5% below standard indicating pilferage, process loss, or measurement error |
| Scrap register verification | Verify that scrap generation is recorded in the scrap register with date, type, quantity, and source | Scrap register not maintained; scrap entries only at sale - not at generation |
| Scrap sale verification | Verify scrap sales against invoices, weighment slips, and cash/bank receipts | Scrap sold but not invoiced; scrap sold below market rate to related parties; GST not charged on scrap sale |
| Scrap value in accounts | Verify that scrap value is credited to production cost or shown as other income | Scrap income not recognised; scrap sold for cash and not recorded |
Manufacturing Stock Audit Process: Step-by-Step
1. Pre-audit planning: Understand the factory and production process.Visit the factory layout. Identify all storage locations (RM store, WIP on production lines, FG warehouse, scrap yard, job worker locations). Obtain the BOM for top products. Review the production flow - from RM receipt to FG dispatch. Use ABC analysis to classify items by value - ensuring 100% count of A items and sampling for B/C items.
2. Freeze or control production during the count. Ideally, production is halted during the physical count (weekend or shift-end). If production cannot stop, implement strict cutoff procedures - no material movement between stages during counting hours. Tag in-transit items. This is the most critical step - without production freeze, WIP counts are unreliable.
3. Deploy teams category-wise: RM, WIP, FG, Scrap. Team A: Raw material store - count RM by item, batch, location. Team B: Production floor - count WIP at each stage, note completion %. Team C: FG warehouse - count FG by product, batch, location. Team D: Scrap yard + stores/spares. Each team records quantities with bin/rack references.
4. Reconcile physical count with ERP/stock register. For each item: Physical quantity vs ERP closing balance as of the count date. Categorise discrepancies: shortage, excess, location mismatch, unit-of-measurement error, posting delay (GRN/issue voucher not entered). Investigate all material discrepancies.
5. Verify valuation - RM at purchase cost, WIP at cost + conversion, FG at full cost. RM: Verify cost per unit from purchase invoices using FIFO/weighted average. WIP: Verify RM component + conversion cost (direct labour + overhead allocation at normal capacity). FG: Verify full cost per BOM. Assess NRV for all categories - write down if NRV < cost.
6. Conduct yield and scrap analysis. For top products: RM issued (per production records) minus FG produced (per FG inward) = total process output. Compare actual yield % against BOM standard yield %. Variance = scrap + process loss + potential pilferage. Reconcile with scrap register and scrap sales.
7. Prepare the stock audit report.Report includes: category-wise physical vs book reconciliation, discrepancy analysis with root causes, valuation review (Ind AS 2 compliance), NRV assessment for slow-moving items, yield/scrap analysis, drawing power computation (for bank borrowers), insurance adequacy review, and recommendations for control improvements. Employers filing GST return filing must ensure that scrap sales are invoiced with GST, and that stock discrepancies are reconcilable with GSTR-3B purchase/sales data.
Worked Example: WIP Valuation for an Auto-Component Manufacturer
The following example shows how WIP is valued at the machining stage for a manufacturer producing 1,000 units of a component.
| Cost Component | Calculation | Amount Per Unit (Rs) | Total for 1,000 Units (Rs) |
|---|---|---|---|
| Raw Material (steel billet per BOM) | 2.5 kg x Rs 80/kg | Rs 200 | Rs 2,00,000 |
| Direct Labour (machining stage) | 0.5 hours x Rs 120/hour x 60% completion | Rs 36 | Rs 36,000 |
| Fixed Overhead (at normal capacity) | Normal capacity 50,000 hours/year; Fixed OH Rs 30 lakh/year; Rate = Rs 60/hour; 0.5 hrs x 60% completion | Rs 18 | Rs 18,000 |
| Variable Overhead | Rs 25/hour x 0.5 hours x 60% completion | Rs 7.50 | Rs 7,500 |
| Total WIP Cost at Machining Stage | Rs 261.50 | Rs 2,61,500 |
Key Points: (1) RM is 100% added at the start of machining - full RM cost is in WIP regardless of completion %. (2) Labour and overhead are added proportionately - at 60% completion, only 60% of labour and overhead is included. (3) Fixed overhead is allocated at normal capacity rate (Rs 60/hour), not actual rate. If actual production is only 40,000 hours but normal capacity is 50,000 hours, the unabsorbed overhead (Rs 6 lakh) is expensed - NOT loaded to WIP. This is the most commonly over-valued component in manufacturing WIP.
Common Mistakes in Manufacturing Stock Audits
Mistake 1: Counting WIP without identifying the production stage. A WIP unit at 20% completion and one at 80% completion have very different values. Simply counting WIP units without noting the stage creates valuation errors. Auditors must record both quantity AND stage for every WIP item.
Mistake 2: Allocating full overhead to WIP when production is below normal capacity. Ind AS 2 requires fixed overhead allocation at normal capacity rate. Under-production means under-absorption - the unabsorbed portion is an expense, not inventory. Loading full overhead to WIP when running at 60% capacity inflates inventory by 40% of fixed overhead.
Mistake 3: Not reconciling scrap with production records. If BOM says 1 kg of steel produces 0.85 kg of output (15% scrap), then 10,000 kg of steel should produce 8,500 kg of output and 1,500 kg of scrap. If actual scrap is only 1,000 kg, 500 kg is missing - either unrecorded scrap sales, pilferage, or measurement error.
Mistake 4: Not verifying stock at job workers. Raw materials or semi-finished components sent to job workers for surface treatment, heat treatment, or testing are often "out of sight, out of mind." The stock register may show the items as issued, but the job worker may have already returned or consumed them. Physical verification or written confirmation is essential.
Mistake 5: Not conducting cutoff analysis for production movements. If RM is issued to production at 3 PM but the physical count was at 2 PM, the same material could be counted as RM (by the RM team) and as WIP (by the WIP team) - double-counted. Strict production freeze or rigorous cutoff procedures prevent this.
Documents Required for Manufacturing Stock Audit
- Bill of Materials (BOM) for all products - RM components, quantities, standard yield
- Production orders / job cards with status (open, closed, completed)
- Material issue vouchers (RM issued from store to production)
- Production output records (FG produced, batch-wise)
- Scrap register with date, type, quantity, and source production line
- GRNs (Goods Received Notes) for RM received during the audit period
- Delivery challans and sales invoices for FG dispatched
- Job worker registers - material sent out, material returned, pending
- ERP stock report as of audit date (item-wise closing balance for RM, WIP, FG, scrap)
- Overhead allocation workings - fixed OH rate, normal capacity basis, actual production hours
- Previous stock audit report - to follow up on earlier observations
- Bank stock statement and sanction letter (for borrower audits)
- Insurance policies covering all inventory locations
- GST returns (GSTR-3B, GSTR-1) for cross-verification
How Manufacturing Stock Audit Affects Bank Drawing Power
For manufacturing borrowers, the bank computes drawing power on total eligible inventory - RM + WIP + FG. Each category has different eligibility rules and margins.
| Inventory Category | Typical Bank Margin | Eligibility Rules | Common DP Reduction Triggers |
|---|---|---|---|
| Raw Materials | 25% | Paid stock only; exclude aged >180 days, damaged, uninsured | RM at job worker not in hypothecation agreement; expired RM |
| WIP | 30-40% (higher margin = higher risk) | Only if properly valued with conversion cost; some banks exclude WIP entirely | WIP not valued with overhead; WIP at uncertain stage; banks wary of WIP as collateral |
| Finished Goods | 25% | Paid stock; exclude FG with no orders >90 days; customer-specific FG if order cancelled | FG made to spec but order cancelled; FG past best-before date; FG in dispute |
| Stores and Spares | 25-30% | Generally included if regularly consumed; exclude capital spares | Spares for discontinued machinery; spares held for 2+ years |
| Scrap | Excluded | Banks do not include scrap in DP - zero value for DP computation | All scrap excluded; scrap sale proceeds reduce RM cost |
How Manufacturing Stock Audit Connects with Other Audits
Manufacturing stock audit connects directly with statutory audit (CARO 2020 reporting on physical verification and material discrepancies), cost audit (verification of cost records, BOM accuracy, and overhead allocation), internal audit (process controls on material receipt, issue, production, and scrap), bank audit (drawing power and stock statement verification), and GST compliance (purchase/sales reconciliation with stock movements).
For manufacturers, the stock audit report is the single document that simultaneously satisfies banking compliance (drawing power), statutory audit support (CARO 2020), cost audit evidence (inventory valuation), and management information (yield analysis, scrap trends, control recommendations). A well-conducted manufacturing stock audit is a strategic tool - not just a compliance exercise.
RM vs WIP vs FG: Audit Approach Comparison
| Feature | Raw Materials | Work-in-Process | Finished Goods |
|---|---|---|---|
| Counting difficulty | Low-Medium (items in bins/racks; bulk requires weighment) | High (items on production lines at various stages) | Medium (items in warehouse; batch/pallet counting) |
| Valuation method | Purchase cost (FIFO or weighted average) | RM + proportionate conversion cost (labour + OH at normal capacity) | Full cost (RM + full conversion cost) |
| NRV assessment | Assess if RM will be consumed in FG that sells above cost | NRV of FG minus costs to complete | Estimated selling price minus selling costs |
| Scrap relevance | Scrap generated from RM cutting/processing must be reconciled | WIP rejection creates scrap; rework cost must be tracked | FG rejection by customer = return or write-down |
| Bank DP treatment | 25% margin; paid stock only | 30-40% margin; some banks exclude entirely | 25% margin; paid stock; orders pending preferred |
| Cutoff risk | GRN timing - received but not posted | Highest - production movements during count create double-count risk | Dispatch cutoff - shipped but not invoiced |
| Third-party stock | RM at job workers (heat treatment, testing) | Rare - WIP usually stays on-site | FG at consignment agents, distributors |
| Audit time allocation | 25-30% of total audit time | 30-35% (most complex) | 25-30% |
Key Takeaways
Manufacturing stock audit covers 5+ inventory categories - raw materials, WIP (at multiple production stages), finished goods, stores/spares, and scrap - each requiring a different counting method, valuation approach, and reconciliation technique. Generic trading audit approaches are inadequate for manufacturing complexity.
WIP is the most challenging category: the auditor must verify both physical quantity and stage of completion. WIP valuation includes RM cost + proportionate direct labour + proportionate manufacturing overhead allocated at normal capacity. Under-production overhead must be expensed, not loaded to WIP - this is the most commonly over-valued component.
Scrap reconciliation is where manufacturing audits find hidden value (or hidden losses). The formula is simple: RM input minus FG output = scrap + process loss. If actual scrap is less than expected, the missing quantity is either unrecorded scrap sales, pilferage, or measurement error. Scrap can represent 3-8% of RM cost in auto-component manufacturing.
For bank borrowers, each inventory category has different DP treatment - RM at 25% margin, WIP at 30-40% (or excluded by some banks), FG at 25%, scrap excluded entirely. A manufacturing stock audit that correctly classifies inventory into these categories provides accurate DP computation - preventing both over-drawing and unnecessary credit restriction.
Production cutoff is critical. Without freezing production during the count (or implementing rigorous cutoff procedures), the same material can be double-counted - as RM and as WIP, or as WIP and as FG. Weekend/shift-end counting coordinated with the production schedule minimises this risk.
Need a Manufacturing Stock Audit?
Manufacturing stock audit requires CA teams experienced in production environments - who understand BOMs, conversion costing, overhead allocation, scrap reconciliation, and multi-stage WIP verification. Generic counting services that work for trading companies are inadequate for factory-floor complexity.
Explore our stock audit services - on-site physical verification of RM, WIP, FG, and scrap with production-integrated counting, BOM-based yield analysis, Ind AS 2 valuation, drawing power computation, and CARO 2020 support. Experienced across auto-components, pharma, chemicals, FMCG, textiles, and electronics manufacturing.
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