A buy-two-get-one-free offer does not always mean one-third off your basket. If the lowest-priced eligible item is free, the saving depends on which three prices you combine. Start with the items you need, then apply the promotion’s actual free-item rule.
The prices and promotion rules below are hypothetical. They explain the calculation, not a current retailer sale or a promise that any particular products qualify.
Equal prices give the familiar one-third saving
Suppose three eligible items each cost $12, and the cheapest one becomes free. Their combined price before the offer is $36. Subtract one $12 item and you pay $24 before tax and other charges. The $12 saving is one-third of $36, or about 33.3%.
That result relies on three equally priced items. It does not describe every basket carrying the same promotion label.
| Three eligible item prices | Total before offer | Cheapest item free | Amount due before tax | Saving versus all three at those prices |
|---|---|---|---|---|
| $12 + $12 + $12 | $36 | $12 | $24 | About 33.3% |
| $12 + $12 + $4 | $28 | $4 | $24 | About 14.3% |
| $12 + $8 + $4 | $24 | $4 | $20 | About 16.7% |
A cheaper third item changes the value, not always the cash paid
In the second row, the two $12 items still cost $24. The offer adds the $4 item without increasing that merchandise total. If the two $12 items were your complete shopping list, you have received an extra item but have not reduced the cash needed to buy the original pair.
That can be useful when the third item replaces another planned purchase. If it will go unused, its sticker price is not a saving in your household budget. Choose an item you can use rather than trying to maximize the displayed discount alone.
Read the grouping rule for larger baskets
Six eligible items do not tell you which two will be free. The terms may describe grouping, the number of qualifying groups, item or account limits, and how the discount is allocated. Read those terms before calculating a larger order; do not assume the register will form the most valuable groups for you.
Also check whether mixing categories or brands is allowed and whether a coupon changes eligibility or the free-item calculation. Do not add a second promotion to the math unless the combination is permitted. A crossed-out reference price is not the amount you are paying for the required items.
Compare the offer with buying less
Take the $12, $8 and $4 basket above. The promotion total is $20. If you only needed the $8 item, buying that one alone would cost $8 before other charges. The three-item offer would require $12 more cash, even though it discounts the larger basket.
Write down two totals: your planned purchase without the extra items, and the complete qualifying basket after the promotion. Then decide whether the additional useful items justify the difference. This is especially important when the offer encourages a larger pack or an unfamiliar substitute.
Use the right comparison for the offer
- Record the exact qualifying items, quantities and current prices.
- Identify which item becomes free and any grouping or purchase limits.
- Calculate the merchandise total, then add the shipping, tax and fees that apply to your order.
- Compare with buying only what you planned; keep later rewards separate.
For ordinary buy-one-get-one offers, use our BOGO grocery comparison. The promotion name sets the starting rule; the exact basket determines your useful saving.