SHOPPING MATH GUIDE

Buy One, Get One 50% Off: What Is the Real Discount?

See why a half-price second item means 25% off when both items cost the same, and why different prices change the savings.

4 min read

THE SHORT ANSWER

For two equally priced items, the overall discount is 25%

Only the second item is half off. When both items cost the same, the savings apply to one of the two items, so the full purchase is 25% off—not 50% off.

Start with two $20 items

Picture a store sign that says, “Buy one, get one 50% off.” You pick up two items that normally cost $20 each. The first stays at $20, and the second drops to $10.

Without the promotion, you would pay $40. With the promotion, you pay $30. That is a $10 saving on a $40 purchase, or 25% off overall.

Scroll sideways to see the full table.

How common promotions compare when both items cost $20
OfferTotal paidAmount savedOverall discount
No promotion$40$00%
Second item 50% off$30$1025%
25% off both items$30$1025%
Second item free$20$2050%

Use the full, pre-discount purchase as the baseline

The 50% on the sign describes the second item, not the entire order. To find the actual percentage off the purchase, divide the amount saved by what both items would normally cost.

Overall discount(Price of the discounted item × 0.50) ÷ regular price of both items × 100

For two $20 items, that becomes ($20 × 0.50) ÷ $40 × 100 = 25%.

What if the two items have different prices?

If the discount applies to the lower-priced item, the overall savings fall below 25%. For example, if one item costs $30 and the other costs $20, taking 50% off the $20 item saves $10 on a $50 purchase. The real discount is 20%.

Scroll sideways to see the full table.

Overall discount when the lower-priced item is half off
Item pricesSavingsOverall discount
$20 and $20$1025%
$30 and $20$1020%
$50 and $10$5About 8.33%

Check the promotion’s terms before assuming which item gets the discount. If the higher-priced item is discounted instead, the result changes.

Half off the second item is not the same as a free second item

For two equally priced items, “buy one, get one free” saves 50% overall. “Buy one, get one 50% off” saves 25% overall. Both deals require two items, but the free-item promotion saves twice as much in this example.

The calculator below handles free-item offers only. Use it when you want to compare this half-price promotion with a true buy-one-get-one-free deal.

Check whether the deal fits your purchase

  • Do you need two items? The promotion only helps if buying the second item makes sense for you.
  • Which item gets the discount? The savings depend on whether the lower-priced or higher-priced item is reduced.
  • Would a regular percent-off sale cost less? Compare the final checkout total, not just the largest percentage on the sign.
  • Are there restrictions? Check which products qualify and whether coupons or other promotions can be combined.