Updated 12 August 2026
Microsoft calls it a product key. Half the internet calls it a licence key. Somebody on a marketplace is selling you an “activation key”, and your PC says you have a “digital licence”. Four names, one thing.
They are all the same 25-character code — or, in the case of a digital licence, the same entitlement stored a different way. Here is what each term actually means, and the one distinction that does matter when you buy.
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Windows 11 Home and Pro, delivered by email
Genuine perpetual licences with a lifetime warranty and UK support seven days a week. Home from …, Pro from ….
- Product key Microsoft’s official term. A 25-character code in five groups of five, entered during installation or in Activation settings to prove your copy of Windows 11 is genuine.
- Licence key The same code. “Licence” emphasises what you are buying — the right to use Windows — rather than the code itself. No functional difference.
- Activation key The same code again, named after what you do with it. Common on reseller listings and in forums; Microsoft does not use it as a product name.
- Digital licence A different delivery method, not a different product. Your entitlement is held against your device hardware and, optionally, your Microsoft account — so there is no code to type in. Windows 11 documentation also calls this a digital entitlement.
- Digital download key Marketing language for a product key sent by email rather than printed on a card or sticker. Same code, different postage.
- Retail / OEM / Volume This is the distinction that actually matters. Not what the key is called, but what type of licence sits behind it — it decides whether you can move it to a new PC. See the comparison below.
What a Windows 11 product key looks like
Every Windows 11 product key follows the same format: 25 alphanumeric characters, split into five blocks of five, separated by hyphens.
Format only. Never enter a key you have found published on a website or forum.
If a seller offers you something that is not in this format — a download link, an account login, an “activator” tool, or a script — it is not a Windows 11 licence. Account-sharing and activation tools are not licensing, and Microsoft can block the resulting installation at any time.
Licence key vs product key: is there any difference?
No. They are two names for the same 25-character code, in the way that “car” and “automobile” describe the same vehicle.
The reason both terms exist is that they describe two halves of the same transaction. The licence is the legal permission to run Windows 11 on a PC. The key is the mechanism that proves to Microsoft’s activation servers that you hold that permission. Microsoft’s own documentation tends to say “product key” when talking about the code and “licence” when talking about your rights — which is precisely why the two words get bolted together into “licence key” everywhere else.
For you as a buyer, the practical answer is simple: if a UK seller lists a “Windows 11 licence key” and another lists a “Windows 11 product key”, they are selling the same thing. Judge them on licence type, price and after-sales support instead.
Activation key, digital licence and digital entitlement
“Activation key” is the third synonym and needs no further explanation — same code, named after the job it does.
A digital licence is genuinely different, but not in the way most people assume. It is not a better or worse licence. It is the same entitlement stored without a code you have to handle. Windows records the activation against your device’s hardware, and if you sign in with a Microsoft account, links it there too. Activation then happens automatically once the PC is online — nothing to type, nothing to lose.
Windows 11 uses both methods side by side. You get a digital licence if you upgraded from an activated Windows 10 installation, bought a PC with Windows pre-installed, or bought Windows through the Microsoft Store. You get a product key if you bought a boxed or downloadable licence from a retailer or reseller. Once you have entered a key, Windows typically converts it into a digital licence on that device anyway — which is why the two terms end up used interchangeably.
Worth knowing: a digital licence tied only to hardware can fail after a motherboard replacement, because Windows no longer recognises the device. Linking it to a Microsoft account first gives you a route back via Settings → System → Activation → Troubleshoot. If you hold a product key instead, you simply re-enter it.
Retail vs OEM vs Volume: the difference that does matter
If you are going to worry about one piece of Windows 11 licensing terminology, make it this one. The name on the listing is noise; the licence type behind the key determines what you are actually allowed to do with it.
| Licence type | Who it is for | Move to a new PC? | Safe to buy second-hand? |
|---|---|---|---|
| Retail | End users buying Windows separately from the hardware | Yes — one PC at a time, subject to licence terms | Yes, from a reputable seller |
| OEM | PC manufacturers and system builders | No — tied to the first machine’s motherboard | Only with the original hardware |
| Volume / KMS | Organisations activating many devices under an agreement | Not applicable — managed by the organisation | No. These should never be sold to consumers |
The very cheap keys that circulate on auction sites and code marketplaces are overwhelmingly misused Volume keys. They often activate on day one, which is why the listings hold their ratings — and then get blocked in batches once Microsoft identifies the source. What you are left with is a machine that reverts to an unactivated state, personalisation switched off, and a persistent watermark.
How to check what you already have
Before you buy anything, check what is on the machine. Windows tells you which activation method it is using in plain English.
- Open Settings — press
Win + I. - Go to System → Activation.
- Read the Activation state line. “Windows is activated with a digital licence” means no key is needed on this device. “Windows is activated using your organisation’s activation service” means you are on a Volume/KMS licence — worth investigating if this is a personal PC.
- To enter a new key, expand Change product key, select Change, and paste the 25-character code. You can also enter it during a clean installation.
- If activation fails after a hardware change, use Troubleshoot on the same screen and sign in with the Microsoft account the licence was first activated on.
Microsoft’s own guidance on locating a key that came with a PC or a boxed copy is here: Find your Windows product key. For post-upgrade activation problems, see Reactivating Windows after a hardware change.
What a genuine Windows 11 licence should cost
A Windows 11 licence is perpetual. You buy it once, and it runs for the supported life of that installation — there is no renewal, no annual fee, and no subscription to cancel. So the five-year cost of ownership is simply the purchase price, which makes comparison unusually straightforward.
Five-year cost of a genuine Windows 11 licence
One-off purchase, no renewals — total cost over five years
Microsoft Store UK prices checked August 2026. Our prices load live from our store.
The gap is not a discount on a lesser product — the code is identical and activates identically. It reflects where the licence came from and the fact that we are not carrying Microsoft’s retail overheads. What it should never reflect is a Volume key sold outside its agreement, which is where the £3 listings come from.
How to make sure your key is genuine
There is no tool that will tell you in advance whether a key you are about to buy is legitimate — activation is the test, and by then you have paid. So the checks are all about the seller, not the code.
- Check the licence type is stated. A seller who will not tell you whether a key is Retail or OEM is telling you something.
- Look for a warranty, not a returns window. A 14-day return does nothing if the key is blocked in month four.
- Find the support channel. Named contact details and a phone or email route that a person answers, rather than a marketplace message box.
- Be suspicious of the very bottom of the market. Genuine Retail licences have a floor price. Anything far below it came from somewhere it should not have.
- Keep proof of purchase. It is what gets a licence reissued if you ever need to prove entitlement.
Every key we sell at Software Supplies is genuine, comes with a lifetime warranty, and is backed by UK support seven days a week. If a licence ever stops activating, we replace it — that is the whole point of buying from a business with an address rather than a username.
Which Windows 11 edition do you need?
The terminology is interchangeable, but the edition is not. This is the decision worth spending a minute on.
Windows 11 Home covers everything most households and students need — the full operating system, security updates, and the standard feature set.
Windows 11 Pro adds BitLocker drive encryption, Remote Desktop host, Group Policy, Hyper-V and domain join. If you work from home on a machine holding client data, or you run a small business, Pro is the one — and the upgrade costs far less bought as a licence than through the in-Windows upgrade route.
You can compare and buy both here: Windows 11 product keys.
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Operating Systems, Software, Windows, Windows 11 Product Keys – Home & Pro Editions
Original price was: £119.99.£38.00Current price is: £38.00. Add to cart -
Operating Systems, Software, Windows, Windows 11 Product Keys – Home & Pro Editions
Original price was: £114.99.£34.00Current price is: £34.00. Add to cart
Frequently asked questions
No. All three terms describe the same 25-character code used to activate Windows 11. “Product key” is Microsoft’s official term; “licence key” and “activation key” are informal variants used by resellers, forums and tech sites. There is no difference in what you receive or how it works.
A digital licence — also called a digital entitlement — is an activation held against your device’s hardware and, optionally, your Microsoft account, rather than issued as a code you type in. It is the same entitlement, stored differently. Windows 11 supports both methods, and entering a product key usually creates a digital licence on that device.
Go to Settings → System → Activation, expand Change product key, select Change, and paste the 25-character code. You can also enter it during a clean installation when prompted.
Home suits students, families and everyday use. Pro adds BitLocker, Remote Desktop host, Group Policy, Hyper-V and domain join, which matters for business machines and anyone holding client data. Compare both on our Windows 11 product keys page.
Retail keys are sold to end users and can move to a new PC, one machine at a time, subject to licence terms. OEM keys ship with new PCs and are tied to the first machine’s motherboard. Volume and KMS keys are issued to organisations under an agreement and should never be resold to consumers — most blocked “bargain” keys are misused Volume keys.
One at a time. A Retail licence can be moved to a replacement PC once it has been removed from the old one. Significant hardware changes — a new motherboard in particular — usually require reactivation, either by re-entering the key or by signing in with the linked Microsoft account.
Yes. Install Windows 11 — a clean install from USB media gives the most reliable result — then activate with your Windows 11 key in Settings → System → Activation. Windows 10 reached end of support in October 2025, so upgrading is the route back to receiving security updates on unmanaged consumer devices.
It may activate initially. Very cheap keys are typically Volume licences sold outside their agreement, and Microsoft blocks them in batches once the source is identified. The machine then reverts to an unactivated state with personalisation disabled and a desktop watermark, and there is rarely a seller left to contact.
Open Settings → System → Activation. “Windows is activated with a digital licence” or “activated using a product key” both confirm a valid activation. “Activated using your organisation’s activation service” on a personal PC indicates a Volume/KMS key, which is worth investigating. If you see an error code, run the Activation Troubleshooter on the same screen.
Genuine Retail keys are perpetual — they do not expire, and there is no renewal. Retail licences are generally not region-locked, though licence terms are written per region. Keep your proof of purchase from a UK seller either way.
This error means Windows could not reach a Key Management Service, which usually indicates a Volume/KMS key on a machine that is not on the issuing organisation’s network. Check your internet connection and confirm the key you were sold is a Retail licence. If it is, our support team can look at it with you.
A Retail licence can usually be transferred. Remove or deactivate it on the old machine, then activate the new one with the same key or Microsoft account. OEM licences cannot be transferred — they stay with the motherboard they were first activated on.
From Software Supplies, with delivery by email and UK support seven days a week: Windows 11 Home and Windows 11 Pro, or browse all Windows 11 editions.
Gary Walsh is the Head of Tech Support at Software Supplies, with more than 20 years in the IT industry. Fully Microsoft-certified and experienced across the full business software stack — from Windows and Office to cloud infrastructure and device management — Gary delivers practical, no-nonsense advice that helps users and businesses get the most from their technology.
