What "3 for 2" actually means

With a 3 for 2 deal, you put three items from the same promotion in your basket and only pay for two of them at the checkout. In effect, the third item is taken off for free, and it is usually the cheapest of the three automatically. The wording sounds like a generous gift, but in terms of the maths it is a perfectly ordinary discount at a fixed percentage.

As with other multi-buy discounts, the deal almost always applies only within a particular category or promotion group, not to any three items from the whole shop. Which items count is normally stated right next to the promotion itself.

The real discount is one third

If you pay the price of two items for three, you save a third of the total, so roughly 33 per cent. That is less than "one item free" might suggest at first glance, because the free item is spread across three.

By comparison, a buy one get one free deal saves you half, because the free item is only spread across two. The more items you have to buy to get the free share, the smaller the discount becomes in percentage terms, even if the advertising sounds much the same.

Whether a discount code entered on top brings the price down any further depends on the shop. Codes are often excluded from multi-buy deals such as "3 for 2", because the deal already amounts to a fixed discount in itself. Looking at the total in your basket tells you more reliably than entering the code whether the two savings really add up.

A worked example with three items at the same price

Say a shower gel costs 5 euros and you put three bottles in your basket as part of a 3 for 2 deal. Without the discount you would pay 15 euros. With the deal you only pay for two bottles, so 10 euros, and get the third one on top. That brings the price per item down from 5 euros to 3.33 euros a bottle.

Across the whole order, you save 5 euros out of 15 euros, which is exactly 33.3 per cent. That matches the one third from the previous section.

When the three items cost different amounts

If you put three items at different prices in your basket, it is usually the cheapest of the three that becomes free, and you pay full price for the two more expensive ones. Say you add one product for 18 euros, one for 12 euros and one for 6 euros, making 36 euros in total. The cheapest item at 6 euros is dropped, and you pay 30 euros.

That is a discount of 6 euros on 36 euros, or roughly 16.7 per cent, clearly less than the one third you get with items at the same price. The bigger the price gap between the three items, the smaller the discount on the whole order in percentage terms, because the amount taken off always depends on the cheapest item.

What the real price per item tells you about the deal

The price per item, meaning what each single item costs once the discount has been taken off, shows more clearly than the percentage whether a purchase is worth it. In the example with the 5-euro bottles, the price per item drops to 3.33 euros. If you compare that figure with the price per item for the same quantity from another seller without a promotion, you can see straight away whether the 3 for 2 deal is actually cheaper, or whether the starting price was already set higher than elsewhere.

With items at different prices, it no longer makes sense to give a single price per item, because each item benefits by a different amount. Here, checking the total in your basket before you pay helps more than working it out per item.

When the deal is worth it for you

A 3 for 2 deal only really saves you money if you would have needed three of the item anyway. If you buy a third item only because it looks free on paper, you end up spending more than you would on a single, targeted purchase without the promotion.

This is especially true of goods that do not keep for long, or items you realistically will not use three of. The deal also only works in steps of three. If you need four or five, you pay full price for the rest, or you top up to six and are left with things you had not planned for.

What to check before you pay

• Check whether all three items really belong to the same promotion group, or whether a narrower selection applies.
• Look at the basket to see exactly what amount is being taken off, rather than relying on the advertising.
• With items at different prices, work out the real discount as a percentage before comparing the deal with a standard percentage discount.
• Ask yourself whether you would have bought the third item without the promotion.

How the maths behind a buy one get one free offer works is explained in the article Working out buy one get one free deals. You can read how a quantity-based discount scale works in the article Tiered discounts explained. What a free item is worth compared with a discount is covered in the article A free item instead of a discount. You can find current multi-buy deals by category on the categories page.

Frequently asked questions

With "3 for 2", is it always the cheapest item that is free?

In most cases, yes, because that works out best for the shop. You only know for sure from the amount taken off in the basket, though, as an individual shop can set the rule differently.

Is a 3 for 2 deal always better than a percentage discount?

Not automatically. With items at the same price it is worth about 33 per cent off, and with items at different prices it is worth less. A high percentage discount on every single item can be cheaper, especially if the prices of the three items are far apart.

What happens if I only buy two items instead of three?

Then the deal usually does not apply at all, because it is tied to a minimum of three items. You simply pay full price for the two items, with no discount.

Is a 3 for 2 deal worth it on expensive individual items?

That depends on whether you really need them. In percentage terms you save just as much as on cheaper items, and in euros you save even more. But if you have no real need for three, it is still extra spending rather than a saving.