Why Inventory Valuation Matters
Every business ends a month or year with some products still sitting on the shelf. Those unsold items aren’t just products—they’re money. And to understand your true profit, you need to know what that leftover inventory is worth.
At its core, inventory valuation is about assigning a dollar value to what you haven’t sold yet. That number affects:
- your assets on the balance sheet
- your Cost of Goods Sold (COGS)
- your reported profit
- your tax bill
A small change in valuation can shift your financial picture more than you might expect.
The Simple Idea
What it is: Putting a dollar value on your unsold products.
Why it matters: It shows how much cash is tied up in inventory and how much profit you actually made.
The core formula: Starting Inventory + Purchases − COGS = Ending Inventory
This formula is the backbone of inventory accounting. Everything else is just choosing how to calculate the “COGS” part.
How It Works: The Methods (Using Lemons)
Imagine you run a lemonade stand and buy lemons in two batches:
Batch 1: 100 lemons @ $0.10 = $10
Batch 2: 100 lemons @ $0.20 = $20
You sell 150 lemonades. Now you need to decide which lemons you “used” for those sales. That’s where valuation methods come in.
FIFO (First-In, First-Out) – assumes you sell your oldest inventory first.
COGS: 100 @ $0.10 + 50 @ $0.20 = $20
Ending inventory: 50 @ $0.20 = $10
FIFO often shows higher profits when costs are rising because you’re using cheaper, older inventory first.
LIFO (Last-In, First-Out) – assumes you sell your newest inventory first. (Allowed in the U.S., not in many other countries.)
COGS: 100 @ $0.20 + 50 @ $0.10 = $25
Ending inventory: 50 @ $0.10 = $5
LIFO usually results in higher COGS and lower profit when prices rise.
Weighted Average Cost (WAC) – smooths everything out by averaging the cost of all units.
Average cost: $30 ÷ 200 lemons = $0.15 each
COGS: 150 @ $0.15 = $22.50
Ending inventory: 50 @ $0.15 = $7.50
This method avoids the extremes of FIFO and LIFO.
The Bottom Line
The inventory valuation method you choose directly affects your profit, your taxes, and your financial statements. It’s not just an accounting technicality. It’s a strategic decision that shapes how your business is measured and understood.
Interested in learning more? Book a Discovery Call today!
