Methods to Ascertain the Cost of Materials in Production

Every product you see on a shop shelf started life as raw material sitting in a supplier’s warehouse. Before a factory can decide what to charge for that product, it first needs to know exactly what the material cost it. That sounds simple, but the invoice price alone rarely tells the full story. Discounts, freight bills, customs duty, and even the cost of the packaging can all change the final number. Getting this calculation right is the foundation of accurate material costing, and it directly affects pricing, profitability, and inventory valuation.

Why the invoice price is just the starting point 🔗

When a purchase manager buys raw material, the supplier’s invoice shows a price. But that figure is rarely the true cost of the material once it reaches the factory floor. Between the supplier’s warehouse and your store room, several additions and deductions happen: some amounts get subtracted because they are essentially discounts on the price, while others get added because they are expenses genuinely incurred in getting the material ready for use. The Cost Accounting Standard on Material Cost issued by the Institute of Cost Accountants of India lays down exactly this principle: material should be valued at the purchase price plus duties, freight, and other directly attributable expenses, net of trade discounts and refundable taxes.

Cash discount: why it stays out of the cost sheet 🔗

A cash discount is the reduction a supplier offers when a buyer pays early or within a specified credit period. For example, a supplier might offer 2 percent off if the bill is cleared within 10 days instead of the usual 30. It feels like a saving on the material, but from a costing point of view, it isn’t treated that way.

Cash discount is essentially a reward for prompt payment, not a reduction in the value of the goods themselves. It is a financial or treasury matter, similar to interest income, rather than a purchasing matter. Because of this, cash discount is generally excluded from the cost of materials and is instead recorded separately in the books as other income. This distinguishes it clearly from a trade discount, which behaves very differently in the cost sheet, as the next section explains.

Trade and quantity discounts: straightforward deductions 🔗

Unlike cash discount, both trade discount and quantity discount are deducted directly from the purchase price before the cost of material is arrived at. These are not financial rewards; they are adjustments to the actual price of the goods.

Trade discount 🔗

A trade discount is a routine reduction from the supplier’s list price, usually given because the buyer belongs to a particular trade or business category. If the listed price of a material is ₹500 per unit and the supplier allows a 10 percent trade discount, the effective purchase price used for costing becomes ₹450, not ₹500. This discount never even appears as a separate line in the accounting records; the transaction is simply recorded net of the discount.

Quantity discount 🔗

A quantity discount is offered when a buyer purchases in bulk. A supplier might charge ₹450 per unit for orders below 1,000 units but drop the rate to ₹430 per unit for orders above that threshold. Like trade discount, this is also deducted from the invoice price while computing material cost, since it genuinely lowers what the buyer pays for each unit. The valuation approach followed in cost accounting treats both trade and quantity discounts identically in this respect.

Transportation and other direct charges: what gets added 🔗

Once the price has been settled, the material still has to travel from the supplier’s premises to the buyer’s factory or store. Every rupee spent in making this happen is a genuine cost of acquiring the material and must be added to arrive at its true cost.

This includes freight or carriage inward, cartage, loading and unloading charges, and insurance paid while the goods are in transit. If inward freight is incurred, it forms part of the cost of procurement and should be apportioned to the materials on a rational basis, such as weight or number of units, as prescribed under the cost accounting standard’s guidance note on material cost. Handling charges specifically incurred for a batch of material, and storage costs directly attributable before the material is ready for use, are also generally added, though routine warehousing overheads are usually kept separate.

Customs duty and taxes on imported material 🔗

Materials sourced from outside India involve an additional layer of cost: customs duty. This is a charge levied by the government when goods cross the international border, and it must be added to the material cost since it is unavoidable and directly tied to getting the goods into the country.

The true cost of an imported material, often called its landed cost, includes the product price, freight, insurance, customs duty, and other port or clearance charges. Basic customs duty rates are notified from time to time by the customs authorities, and businesses need to track these updates closely, since even a small rate change can shift per-unit material cost noticeably.

Taxes and duties are not always added in full, though. Any tax for which the buyer can later claim credit, such as input tax credit under GST, is excluded from material cost, because it will eventually be recovered from the government rather than being a real expense. Only non-recoverable duties and taxes stay in the cost of material.

Cost of containers and packing material 🔗

Many raw materials, especially liquids, chemicals, and powders, arrive packed in containers, drums, or sacks. Whether this packing cost forms part of the material cost depends on the type of container involved.

Non-returnable containers 🔗

If the container is not meant to be sent back to the supplier, such as a chemical drum that the buyer keeps or discards, its cost is added to the cost of the material, since the buyer has effectively paid for it as part of the purchase.

Returnable containers 🔗

Some containers, such as gas cylinders, come with a refundable deposit. Since this deposit is recoverable once the empty container is returned in good condition, it is not treated as part of the material cost. It behaves more like a loan or advance than an expense.

If empty containers are later sold as scrap, that realisable value from selling the empties is deducted from material cost, since it effectively reduces the net amount the buyer has spent to acquire the material.

Bringing it all together: a worked example 🔗

Suppose a manufacturing unit purchases material with a list price of ₹100 per unit for 1,000 units, and the following adjustments apply:

Notice that cash discount does not appear anywhere in this table at all, since it never touches the material cost calculation. This worked example is a simplified illustration to show how the different components interact; real invoices often carry several materials in one consignment, requiring the freight and duty to be apportioned across items in proportion to weight, value, or volume.

Why this precision actually matters 🔗

Getting the cost of materials right isn’t just an academic exercise for the cost sheet. It feeds directly into two critical business decisions: pricing and inventory valuation. If material cost is understated, because a genuine expense like freight was missed, the selling price calculated on top of it will also be too low, quietly eating into the profit margin on every unit sold. If it is overstated, by wrongly including cash discount as a cost, the product may get priced higher than necessary, making it less competitive in the market.

Inventory valuation is affected too. Closing stock in the balance sheet is valued at cost, so any error in ascertaining material cost carries forward into financial statements, affecting reported profit for the period. This is exactly why cost accountants apply a consistent, standardised approach rather than treating each purchase transaction differently.

What do you think? 🔗

What do you think? If a company frequently imports raw material and customs duty rates change mid-year, how do you think it should decide whether to revalue existing stock or apply the new rate only to fresh purchases? And between trade discount and quantity discount, which one do you think gives a business more room to negotiate with suppliers, and why?

References

1. https://dwpivt501gtb6.cloudfront.net/upload/casb/CAS-6-LR-01042017-Revised.pdf
2. https://www.accountingcoach.com/blog/what-is-a-trade-discount
3. https://www.financestrategists.com/accounting/cost-accounting/material-costing/valuation-of-materials-purchased-received/
4. https://taxmanagementindia.com/web/tmi_blog_details.asp?id=396807
5. https://www.investindia.gov.in/blogs/calculation-import-duty-india-formula-online-tools-and-exemptions
6. https://www.cmaknowledge.in/2026/03/cost-accounting-standard-cas-6-material-cost.html