FIFO, LIFO, and Weighted Average: Which Inventory Valuation Method Is Right for Your Business?
How you value your inventory affects your reported profit, your tax liability, and your understanding of true margins. Most business owners do not choose a method deliberately — they use whatever their accounting software defaults to. This guide explains the differences so you can choose intentionally.
Why Inventory Valuation Matters More Than You Think
When you buy the same item at different prices over time, a question arises: when you sell one unit, which cost do you use to calculate your profit?
This is not a trivial question. The answer directly affects:
- Your Cost of Goods Sold (and therefore your gross profit)
- The value of inventory on your balance sheet
- Your taxable income
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A Simple Example to Illustrate the Difference
Imagine you buy a product at three different times:
- January: 100 units at ₹100 each = ₹10,000
- March: 100 units at ₹120 each = ₹12,000
- May: 100 units at ₹140 each = ₹14,000
The question is: what cost do you assign to those 150 units sold?
The answer depends on your valuation method.
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Method 1: FIFO (First In, First Out)
FIFO assumes the oldest stock is sold first. The first items purchased are the first items considered sold.
Using the example:
- 150 units sold = 100 units at ₹100 (the January purchase, first in) + 50 units at ₹120 (50 of the March purchase)
- Cost of Goods Sold = ₹10,000 + ₹6,000 = ₹16,000
- Remaining inventory = 50 units at ₹120 + 100 units at ₹140 = ₹6,000 + ₹14,000 = ₹20,000
When FIFO Is Appropriate
FIFO matches physical reality for most perishable and time-sensitive products. A food retailer, pharmacy, or clothing shop genuinely sells older stock first to avoid expiry or obsolescence. FIFO accounting matches how the business actually operates.
FIFO also tends to report higher profit in a rising price environment (you are costing sales at older, lower prices) and higher inventory values on the balance sheet (remaining stock is valued at newer, higher prices).
FIFO Pros and Cons
Pros: Matches physical reality for many products; balance sheet inventory is valued at more current prices; widely accepted internationally.
Cons: In rising price environments, FIFO produces higher taxable income because COGS is lower (based on older, cheaper purchases).
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Method 2: LIFO (Last In, First Out)
LIFO assumes the most recently purchased stock is sold first.
Using the example:
- 150 units sold = 100 units at ₹140 (the May purchase, last in) + 50 units at ₹120 (50 of the March purchase)
- Cost of Goods Sold = ₹14,000 + ₹6,000 = ₹20,000
- Remaining inventory = 100 units at ₹100 + 50 units at ₹120 = ₹10,000 + ₹6,000 = ₹16,000
When LIFO Is Used
LIFO is primarily used in the United States (where it is permitted under US GAAP) for its tax advantage in rising price environments — higher COGS reduces taxable profit.
Important note: LIFO is not permitted under IFRS (International Financial Reporting Standards), which is the standard used in India, the UK, Europe, the UAE, Malaysia, Singapore, Australia, and most countries outside the US. If your business is in these regions, LIFO is not an option.
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Method 3: Weighted Average Cost (WAC)
WAC calculates a new average cost after each purchase and applies that average to all sales.
Using the example: After all three purchases: Total cost ₹36,000 ÷ 300 units = ₹120 average cost per unit
- 150 units sold at ₹120 average = ₹18,000 COGS
- Remaining 150 units at ₹120 = ₹18,000 inventory
When WAC Is Appropriate
WAC works well for products where individual units are indistinguishable and interchangeable — fuel, bulk commodities, raw materials, liquids. In practice, it is commonly used for general retail and wholesale businesses where items are similar and tracking individual purchase lots is impractical.
WAC smooths cost fluctuations — rapid price changes do not cause dramatic swings in reported profit period to period.
WAC Pros and Cons
Pros: Simple to calculate; smooths price volatility in reporting; widely accepted; administratively easier than FIFO for large volumes.
Cons: Does not reflect the actual flow of goods for businesses where older or newer stock is specifically sold first; balance sheet inventory value may be less current than FIFO.
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Specific Identification: For High-Value Unique Items
A fourth method — specific identification — tracks the actual cost of each individual unit and assigns that specific cost when the unit is sold.
This is practical only for businesses selling unique, high-value items: vehicles, jewellery, art, custom machinery, or serialised equipment. When every unit has a serial number and individual cost, specific identification provides the most accurate COGS.
For businesses selling large volumes of identical items, specific identification is administratively impossible.
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Which Method Should You Choose?
| Business Type | Recommended Method |
|---|---|
| Food, pharmacy, fashion, perishables | FIFO (matches physical flow) |
| Bulk commodities, raw materials, fuel | Weighted Average |
| High-value unique items (vehicles, jewellery) | Specific Identification |
| General retail / wholesale (outside US) | FIFO or Weighted Average |
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Practical Implementation
Your accounting or ERP system should handle inventory valuation automatically once you set the method. Confirm:
Mismatches between what the system calculates and what was filed with tax authorities create reconciliation problems. Alignment between your accounting software, your financial statements, and your tax returns requires consistent use of the same inventory valuation method throughout.
If you are unsure which method your business currently uses, ask your accountant. If you are setting up a new system, make this decision deliberately — it is easier to choose correctly at the start than to change methods later.