Is a buy-two-get-one-free offer really cheaper than the big pack?

An example from the supermarket shelf

Rice in a 400 g bag at 14, with a buy two, get the third free offer, next to a 1 kg bag at 25. The offer means you pay 2 × 14 = 28 and take home 3 × 400 = 1,200 g:

• The offer, 28 for 1,200 g: 23.3333 per kg, the Best value.
• The big bag, 25 for 1 kg: 25 per kg, which is 7.14% more expensive.
• One bag without the offer, 14 for 400 g: 35 per kg, which is 50% more than the offer.

The mistake that flips the answer

It is easy to enter the offer as if it were one bag: 14 for 400 g. Then the big bag looks cheapest by a wide margin, because the free bag never entered the sum. The rule is always everything you pay against everything you get. The same goes for buy three pay for two, or second item half price: add up what you pay, and add up what you take.

Steps

1. In the Unit-price comparison tool, name the first option Offer and enter the full amount you will pay as its price.
2. As the quantity, enter the total weight of all the packs you will receive, including the free one, and pick the unit.
3. Add the big pack as the second option, and the single pack as a third if you want it in view.
4. Read which one is the Best value and the percentage gap.

When the cheapest option is not a bargain

• When you do not need the quantity: 1.2 kg may be more than you use before the product spoils or goes stale.
• When space is tight: three bags take more room than one.
• When the products differ: if the big pack is a better grade, price alone does not settle it.

If you are a seller thinking of running a similar offer, use the same method to see the real price per kilo you will be selling at inside the offer, compare it with your cost before you announce it, then review your pricing with the Selling-price calculator. For percentage discounts, work out the price after the discount with the Discount calculator and enter that.