Why Inventory Ties Up Cash
Inventory is cash on a shelf -- and shelves charge rent
A distributor holds 4,000 units at $25 each and pays 24% a year to carry stock. That is $100,000 of cash sitting on a shelf -- and $24,000 a year just to keep it there.
Inventory is cash you have already spent
Every unit on a shelf was bought with cash the business has not yet recovered. The cash tied up in inventory is the inventory value, the number of units ($Q$) times the unit cost ($c$). Holding that stock is not free: warehousing, insurance, spoilage, and the cost of the capital itself add up to an annual holding (carrying) cost, quoted as a holding rate ($r$) of inventory value per year.
Reading the formula
Inventory value is a stock of frozen cash: 4,000 units at $25 each is $100,000 the business cannot deploy elsewhere. The holding cost is the annual rent on that frozen cash. At a 24% holding rate, that rent is 0.24 x $100,000 = $24,000 per year -- money spent simply to own the stock, before a single unit is sold.
The holding rate captures the full price of letting cash sit idle: storage and handling, insurance and security, shrinkage and obsolescence, and the return that capital could have earned elsewhere. Treat inventory value as a loan the warehouse is holding, and the holding cost as the interest on that loan.
- 1. Inventory value = units x unit cost = 4,000 x 25 = $100,000 tied up.
- 2. Holding cost = holding rate x inventory value = 0.24 x 100,000 = $24,000 per year.
💡 Hint
- 1. Inventory value = 2,000 x 40 = $80,000.
- 2. Holding cost = 0.18 x 80,000 = $14,400.
Check your understanding
- Inventory value is units times unit cost -- cash frozen on the shelf.
- Annual holding cost is the holding rate times inventory value.
- Treating inventory as invested cash makes the cost of holding it visible.