Quick answer: Buy one get one free is 50% off each item, but only when you will actually use both. Divide what you pay by the items you will use, then compare that number with the store brand and your usual price.
Short answer: buy one get one free (BOGO) is 50% off per item, but only if you will use both items. If you only use one, you paid the full shelf price for it and the “free” item went to waste. The best test is simple: divide what you pay by the number of items you will actually use, then compare that to the store brand and your usual price. The BOGO deal calculator does this in seconds.
The BOGO math
Every “buy X, get Y” offer boils down to one number: the price you pay per item.
| Offer | You pay for | You get | Discount per item |
|---|---|---|---|
| Buy 1 get 1 free | 1 | 2 | 50% |
| Buy 1 get 1 at 50% off | 1.5 | 2 | 25% |
| Buy 2 get 1 free | 2 | 3 | 33.3% |
| Buy 3 get 1 free | 3 | 4 | 25% |
| Buy 2 get 2 free | 2 | 4 | 50% |
The formula is:
effective price per item = total you pay ÷ number of items you get
Example: cereal has a $5.00 shelf price. On BOGO free you pay $5.00 for two boxes, or $2.50 per box. On a buy 1 get 1 at 50% off deal you pay $5.00 + $2.50 = $7.50 for two, or $3.75 per box.
The test that matters: items you will use
The discount only exists for items you would have bought anyway. So use this version:
effective price per item used = total you pay ÷ items you will use
| Scenario | You pay | You use | Cost per item used |
|---|---|---|---|
| $5 cereal, BOGO free, you eat both boxes | $5.00 | 2 | $2.50 |
| $5 cereal, BOGO free, you eat one and the other goes stale | $5.00 | 1 | $5.00 |
| $4 bread, BOGO free, you freeze the second loaf | $4.00 | 2 | $2.00 |
| $6 berries, BOGO free, you eat one and toss one | $6.00 | 1 | $6.00 |
If the second item gets used, BOGO is one of the deepest discounts in a grocery store. If it gets thrown away, it is a full-price purchase. USDA estimates that 30 to 40 percent of the U.S. food supply goes uneaten, so be honest about which category your household falls into. See how much food waste costs you a year.
BOGO vs percent-off sales
You can turn any sale into a price per item and compare. Take a $4.00 item:
| Deal | Items | You pay | Per item |
|---|---|---|---|
| Regular price | 1 | $4.00 | $4.00 |
| 20% off | 1 | $3.20 | $3.20 |
| 30% off | 1 | $2.80 | $2.80 |
| Buy 1 get 1 50% off | 2 | $6.00 | $3.00 |
| Buy 2 get 1 free | 3 | $8.00 | $2.67 |
| Buy 1 get 1 free | 2 | $4.00 | $2.00 |
Two takeaways:
- BOGO free beats a 30% off sale only if you use enough of the second item. The break-even is about 1.4 items used ($4.00 ÷ 1.43 = $2.80). If you use just one, the 30% off sale is better ($2.80 vs $4.00).
- BOGO 50% off is only 25% off per item, which is not much better than a regular sale and often not worth buying extra for.
Use the discount calculator for percent-off deals and read are grocery sales actually worth it for how to judge a sale price.
BOGO vs the store brand
A BOGO on a name brand still might not be the cheapest option. Compare the unit price.
Example: a name-brand box of 12 oz cereal is $5.00, BOGO free. The store brand is $2.99 for 12 oz.
- Name brand on BOGO: $5.00 for 24 oz = $0.208 per oz
- Store brand: $2.99 for 12 oz = $0.249 per oz
Here the BOGO wins, if you will eat all 24 oz. If the store brand is on sale at $1.99, it wins again at $0.166 per oz and you do not have to buy two. Use the unit price calculator and see store brand vs name brand and which is cheaper: comparing grocery sizes and units.
Do you have to buy two?
Stores differ, and so do their rules:
- Some stores ring up each BOGO item at half the shelf price, so buying one costs half and you do not need to buy two.
- Others require you to buy two (or buy one and get the second added automatically).
- Manufacturer BOGO coupons generally require buying both items.
- Rules can vary by state and by store, and change over time.
Check the sign, the store’s website or app, or ask a cashier. If a store applies the half-price rule, a BOGO becomes a 50% off sale with no commitment, which makes it much better for perishable foods.
Is the regular price real?
The FTC’s Guide Concerning Use of the Word “Free” (16 CFR Part 251) says that in a “buy one, get one free” offer, the seller should charge no more than the regular price for the item you pay for. The regular price must not be raised to make up for the free item. These are FTC guides, not a price-check service, so you still need to check for yourself.
Quick checks:
- Compare to your price book. If the “regular” price is higher than you have seen for months, the BOGO may not be a bargain. Track prices with the grocery price book.
- Check the size. Smaller packages with the same price are shrinkflation. The Bureau of Labor Statistics defines it as a reduction in package size without a matching price cut. See what is shrinkflation.
- Compare the unit price of the BOGO item with a non-BOGO alternative.
What to buy on BOGO (and what to skip)
Good BOGO buys (you use them, and they last or freeze):
- Pasta, rice, beans, canned tomatoes, canned vegetables
- Cereal, oatmeal, peanut butter, sauces
- Frozen vegetables, frozen fruit, frozen meals
- Bread, tortillas, and bagels (freeze the second)
- Chicken, ground beef, and other meat you can freeze
- Household items you always use
Think twice:
- Fresh berries, greens, herbs, and other produce that spoils in days
- Milk, yogurt, and fresh dairy you cannot finish before the date
- Brands or flavors you have never tried
- Snacks that make you eat more just because you have more
For how long things last, see how long food lasts in the fridge vs the freezer.
Stacking coupons with BOGO
Coupons can make BOGO deeper, but the details matter:
- A store coupon may apply to one item or both. Read the terms.
- A manufacturer coupon usually applies per qualifying item you buy, so a $1 coupon on a BOGO pair might knock $1 off the pair or $1 off each, depending on store policy.
- Stores may limit the number of coupons per transaction.
Run both scenarios through the coupon stacking calculator, then read how to use grocery coupons effectively.
Worked examples
1. Yogurt, 4 cups at $4.80, BOGO free. You pay $4.80 for 8 cups, or $0.60 per cup. Your family eats 4 cups a week and the date is 2 weeks away. You will use all 8. Good deal.
2. Fresh strawberries, $5.00, BOGO free. You eat one container in 4 days. The second will mold before you finish it. Cost per container used: $5.00. Skip, or freeze the second right away.
3. Chicken breasts, 2 lb at $7.00, BOGO free. You pay $7.00 for 4 lb, or $1.75 per lb. You freeze the second pack. Good deal, if your regular price is above $1.75 per lb.
4. Pasta sauce, $3.50, BOGO free, with a store brand at $2.00. BOGO is $1.75 each, and the store brand is $2.00 each. BOGO wins, but only by $0.25 per jar. If you prefer the store brand, the savings are small.
5. Chips, $4.50, BOGO 50% off. You pay $6.75 for two, or $3.38 each. A regular 25% off sale would give you $3.38 for just one bag. No reason to buy extra.
A simple decision checklist
- Would I buy this item anyway? If not, skip it.
- Will I use both before they spoil, or can I freeze them?
- Is the price per item lower than my price book and the store brand?
- Does the store let me buy just one at half price?
- Is the package the same size as last time?
If the answer to all five is yes, buy it.
Quick cheat sheet
- BOGO free = 50% off per item, only if you use both
- Buy 1 get 1 at 50% off = 25% off per item
- Buy 2 get 1 free = 33% off per item
- Effective price = total paid ÷ items you will use
- Check the unit price against the store brand
- Check your store’s half-price policy before buying two
- Freeze, share, or skip perishables
Limits of this guide
Store policies on BOGO pricing and coupons vary and change, so always read the sign and the store’s terms. The prices in the examples are illustrative, not current prices.
Sources
- Federal Trade Commission, Guide Concerning Use of the Word “Free” and Similar Representations (16 CFR Part 251)
- Electronic Code of Federal Regulations, 16 CFR Part 251
- U.S. Bureau of Labor Statistics, Measuring shrinkflation and its impact on inflation
- USDA, Food Waste FAQs
Last reviewed October 7, 2026.
Evergreen method
Measure savings against a clean baseline
A saving is the difference between comparable baskets, not a coupon total or an advertised percentage.
Formula
savings rate = (baseline cost − new cost) ÷ baseline cost × 100Reproducible steps
- 1.Compare the same quantities and quality level.
- 2.Include fees, membership costs and unused products.
- 3.Annualize only after several representative shopping cycles.
Put it to work
Run the numbers for your household
FAQ
Common questions
Is buy one get one free really 50% off?
Yes, per item. You pay for one and get two, so each item costs half the shelf price. A $6 item on BOGO free works out to $3 each, but only if you would use both. If you use just one, you paid full price.
Is BOGO better than 50% off?
They are the same per item if you buy two. BOGO free at $6 gives you two items for $6, and 50% off gives you two items for $6. The difference is that BOGO usually requires buying two, while a 50% off sale lets you buy just one at $3.
How much is buy one get one 50% off?
It is 25% off per item when you buy two. At a $6 shelf price you pay $6 plus $3, or $9 for two, which is $4.50 each. It is a smaller discount than BOGO free, so compare it with simple percent-off sales.
Is buy 2 get 1 free a better deal than BOGO?
Per item it is worse. You pay for two and get three, which is about 33% off, while BOGO free is 50% off. But it can still be a good deal if you would use all three and the base price is fair.
Do I have to buy two items to get a BOGO deal?
It depends on the store. Some stores ring up each BOGO item at half price, so one item costs half the shelf price. Others require two. Manufacturer BOGO coupons almost always require buying both. Check the store's policy or ask at the register.
Is BOGO ever a trick?
It can be if the regular price was raised before the sale, or if the package got smaller. The FTC says the regular price of the item you pay for cannot be inflated to cover the free one. Check your price book and the unit price to be sure.
What does the FTC say about free offers?
The FTC's Guide Concerning Use of the Word Free says that in a buy one get one free offer, the other item should be sold at its regular price. The regular price must not be raised to make up for the free item.
What foods are best to buy on BOGO?
Foods you use regularly that last a long time or freeze well: pasta, rice, canned goods, cereal, peanut butter, frozen vegetables, bread, and meat you can freeze. Skip BOGO on fresh produce, dairy, or anything you cannot finish or freeze before it expires.
Can I use coupons on BOGO items?
Sometimes. Policies vary by store and by coupon. A store coupon may apply to one or both items, and a manufacturer coupon usually applies per qualifying item. Use the coupon stacking calculator to compare outcomes, then confirm the store's rules.
Is a BOGO deal worth it if I only need one?
Only if the store sells it at half price per item, or if you can freeze, share, or store the second one. If you have to pay the full price for two and use one, the BOGO costs more than buying one on an ordinary sale.
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