How to tell a genuine Microsoft licence from a grey-market key

Search for a Windows or Office key and you will find prices from three dollars to three hundred. The cheap ones are not all scams — but they are almost never what the listing says they are. Here is how the market actually works and how to protect yourself.

Where very cheap keys come from

• Volume licence keys (MAK) issued to a company for its own PCs, then sold off one activation at a time. They work until Microsoft notices the pattern and blocks the key — often months later, sometimes within days.
• Education or regional keys meant for students or specific countries, resold outside their terms.
• Stolen card purchases. Someone buys a real key with a stolen card, sells it cheaply, and the original purchase is reversed. The key is then revoked.
• Used retail keys scraped from old installations or second-hand machines, sold as "new".

Each of these can activate on the day you buy it. The problem appears later, usually as "This copy of Windows is not genuine" or Office switching to reduced functionality.

Seven checks before you buy

1. A real company name and address. Not a marketplace handle. You should be able to find the business in a public register. Ours is in the footer of every page.
2. A phone number that a human answers. Grey-market sellers cannot afford support; legitimate resellers build their reputation on it.
3. A money-back promise that is written down, with a time limit and a clear process — not "contact us for issues".
4. The right product name. "Windows 11 Pro Retail Key" is a product. "Windows 11 Pro Key — Global — Lifetime" is a warning sign: "global" usually means a volume key.
5. A price that makes sense. Microsoft's own price for Windows 11 Pro is $199.99. A reseller buying through distribution can legitimately sell for less, but not for the price of a coffee.
6. A product page with real detail — part numbers, system requirements, what the licence can and cannot do.
7. Payment through a recognised processor with card protection, not a crypto wallet or a friends-and-family transfer.

What to do after activation

Whatever you buy, sign in with a Microsoft account after you activate Windows. The licence becomes a digital licence linked to your account, which makes reinstalling later painless. For Office, keep the confirmation e-mail: the product key and order reference are your proof of purchase.

How we source keys

We buy through authorised distribution, one licence per key, and we keep the invoice chain for every batch. That is why our prices sit below Microsoft's list price but nowhere near the grey market — and why we can promise a refund if a key will not activate.

If a key you bought elsewhere has stopped working, our activation help page explains what the error codes mean and what your options are.