How the math works
Multiply the price by one minus each discount in turn. A 25% discount multiplies by 0.75, a 10% discount by 0.90 and a 5% discount by 0.95.
Worked example
Start at $120. Take 25% off to reach $90.00. Take 10% off that to reach $81.00. Take 5% off that to reach $76.95. You saved $43.05, which is an effective discount of 35.87%, not 40%.
The order does not change the final price when every discount is a percentage. It can matter if one is a fixed dollar coupon, because a dollar coupon is worth the same whenever you apply it but a percentage depends on the price it applies to.
Tax and fine print
Sales tax is usually calculated on the discounted price, but rules vary by state and by the kind of coupon. Some stores do not allow certain offers to be combined, so read the terms before you count on a stack.
Try the calculator
Run your own numbers in the free stacked discount calculator. It works in your browser and nothing you enter is saved or sent.
Common questions
Is 20% off and 20% off the same as 40% off?
No. It is 36% off, because the second 20% applies to the already reduced price.
Why does the order not matter?
Multiplication gives the same product in any order.
Do all stores allow stacking?
No. Check the terms of each offer.
This guide is general information, not financial, tax or legal advice. Rates, fees and rules change, so confirm current terms with the lender, store or agency involved. All dollar figures are invented examples.