Two completely different types of discount code
A single-use discount code and a code that is the same for everyone often look identical at checkout: a string of letters and numbers, an input field, a confirmation. Behind them, though, are two fundamentally different types, and they determine how many people can ever enter the same code at all.
Knowing this difference explains why a code you found on a comparison site might work for you, while a code from a personal email should never work for anyone but you.
The code for everyone: one string, many purchases
A code for everyone is a single, fixed string that a shop publishes for a promotion and that, in principle, any customer can enter. Codes like this usually appear in a broad advertising campaign, for example around a particular occasion or season, and stay valid until the expiry date is reached or the shop ends the promotion early. There may still be a usage limit per account, even though the string itself is identical for everyone.
The single-use code: a string of its own for each person
A single-use code, by contrast, is newly generated for one person or one order, often automatically from a combination of random characters. You often find this type with an individual discount code created through a referral programme, or with a promotion issued by customer service as compensation. Two different people will not receive the same string, even if both codes give exactly the same discount.
Why shops use both types at the same time
A code for everyone is a good fit when a shop wants to trigger as many orders as possible within a fixed period, during a seasonal promotion for instance, without having to generate a separate string for every single customer. A single-use code is a better fit when a shop wants to track exactly who received a particular incentive, as with a referral programme, or wants to stop a code being used without control by a huge number of people via a comparison site.
What this means for a list of many discount codes
A site that collects discount codes for many shops can sensibly show almost nothing but codes for everyone, because a single-use code tied to one person would be worthless to every other visitor anyway and would only cause confusion if it appeared there. On our discount codes page you will therefore mostly find promotions intended for a wider group, with their own allowance or a fixed expiry date, rather than codes that were really only generated for a single order.
If an originally individual code does turn up in public, because it was passed on by mistake, for example, in practice it is often used up after the first stranger redeems it, because its allowance was designed for a single use from the start. That sets it clearly apart from a code meant for everyone, which was designed precisely for repeated use by many different people.
A well-maintained list will ideally spot this difference when a code that worked at first is rejected again after a short time, and will then remove it rather than leaving it up unchanged. For you, this means the more recently a source was checked, the more likely it is to show codes for everyone that are still active, rather than a single one-off that was used up long ago.
Worked example: same discount, different origin
Say a basket is worth 40 euros. A publicly published code for everyone brings the price down by 10 percent to 36 euros, and in principle a thousand other people could use the same code for the same discount while the promotion is running. An individual single-use code you received through a referral programme brings the same basket down by the same amount to the same 36 euros, except that this particular string was generated only for your order and cannot be redeemed after that.
How to tell which type you are dealing with
You usually cannot tell from the code itself: a short, generic string can just as easily be a single-use code as a long, random-looking combination can be a code for everyone. Where the code comes from is more reliable. A code from a message addressed to you personally is usually individual, while a code listed on a comparison site is generally meant for everyone, as long as its allowance lasts. Why codes only work once is closely linked to this distinction, but it is not the same question as whether a code is an individual string in the first place. A closer look at the terms around voucher codes, discount codes and promo codes helps you set the right expectations. Why expired codes keep circulating online for so long and how we check codes are explained in two more articles, which show how differently the two types behave in practice.
Frequently asked questions
How can I tell whether a code I found is meant only for me?
Usually not from the code itself, but from where it came from. If it was in a message addressed to you personally, such as a referral or win-back email, it was probably generated individually and is not meant to be passed on.
Can a code for everyone still work only once per account?
Yes, that is actually common. The string itself stays the same for all customers, while in the background the system still checks whether your account has already used it.
Why do some people get a single-use code and others do not?
Single-use codes usually arise from a specific trigger, such as a referral, an abandoned purchase or a customer service enquiry. Without a trigger like that, a shop generally does not create an individual code, but points you to ongoing promotions open to everyone.
Is a code for everyone worth less than a single-use code?
Not in principle; the discount can be exactly the same. The only difference is how many people can redeem the code and how long it stays available for that.
