The Replacement Cost Trap in Inflation: It's Not What You Paid, It's What Restocking Costs
A product that looks profitable against an old invoice may not be restockable at today's wholesale price.
October 16, 2026 · 4 min
Why does your stock shrink while the invoice shows a profit?
Say you bought 500 products two months ago at $100 each. After sales and platform deductions, you keep $130 per product. Against the old purchase cost, that is $30 of contribution. But if today's supply price is $140, you cannot rebuild your 500-unit stock.
The restocking calculation
| Item | Calculation | Result |
|---|---|---|
| Units sold | 500 units | 500 |
| Net collection | 500 × $130 | $65,000 |
| New supply price | $140 per unit | $140 |
| Restockable units | 65,000 ÷ 140 | 464 units (whole products) |
| Loss in stock units | (500 − 464) ÷ 500 | About 7.2% |
Sample calculation. It does not cover tax, financing, deferred payment, inventory valuation or other business cash inflows. After buying 464 products, $40 remains.
How to build replacement cost into your pricing
- Record the supplier's verifiable quote today, not your latest invoice.
- Keep historical purchase cost and replacement cost as two separate data points.
- Test as a scenario whether your demand and competitors will accept the new price.
To complete the cost side of the decision, enter the current supplier quote and the verified purchase price. Also read about the limits of cost data.