Quick Answer
Stacked discounts are applied one after another. They multiply, not add.
Final price = Original price × (1 − discount 1) × (1 − discount 2)
Example: $100 with 20% off, then another 10% off:
- $100 × 0.80 = $80
- $80 × 0.90 = $72
- Total discount = 28%, not 30%
Common Stacked Discounts
| First Discount | Second Discount | You Pay | Total Discount |
|---|---|---|---|
| 10% | 10% | 81% | 19% |
| 20% | 10% | 72% | 28% |
| 25% | 20% | 60% | 40% |
| 30% | 15% | 59.5% | 40.5% |
| 50% | 20% | 40% | 60% |
The second discount applies to the already-discounted price, which is why the total is smaller than simple addition.
Coupon Plus Sale Example
Suppose a jacket is $120, marked 25% off, and you have an extra 15% coupon.
- Sale price: $120 × 0.75 = $90
- Coupon: $90 × 0.85 = $76.50
- Total savings: $120 − $76.50 = $43.50
- Total discount: $43.50 ÷ $120 = 36.25%
It is not 40% off because 25% + 15% is not how stacked discounts work.
Add Tax After Discounts
In most shopping situations, sales tax is calculated after the discount. If the final discounted price is $76.50 and tax is 8%, the total is:
$76.50 × 1.08 = $82.62
Use the sales tax calculator if you need the tax portion separately.
When to Use This
- Store sale plus coupon code
- Black Friday extra discount
- Student or employee discount after sale price
- Bulk discount plus loyalty reward
- Marketplace vouchers and seller coupons
For more general percent math, use the percentage calculator.