Independent guidance for Windows, Office, Server, SQL and the wider Microsoft stack — editions, CALs, Volume Licensing, CSP and the differences that matter at purchase time.
Updated as Microsoft ships SE, LTSC and Dynamics changes — covering 2024 and 2025 editions in depth.
Each channel suits a different size of organisation. Pick the one that matches how you'll use, manage and renew.
Boxed or ESD keys, transferable, registered to a Microsoft account.
MAK / KMS activation, centralized VLSC, optional Software Assurance.
Monthly / annual seats, managed through partner or admin center.
Detailed guidance for every major Microsoft product. Click through for editions, activation models, audit notes and FAQs.
Coverage across the Microsoft stack — depth measured in editions, CAL combinations and licensing paths explained per category.
Plain-English answers to the questions buyers and IT admins actually ask.
Most licensing mistakes trace back to skipping one of these questions. Answer them in order and the correct SKU almost picks itself.
Individual, small team, or an enterprise directory of named users. Named-user models (Microsoft 365, Visual Studio subscriptions) beat device models when people move between machines.
On a laptop, on a VM you manage, or in a shared/RDS host. RDS, VDI and multi-tenant scenarios flip the maths — you need per-user CALs plus RDS SALs, not desktop retail keys.
Retail keys are per-device with a receipt trail. Volume Licensing and CSP give you a portal, a contract, and reassignment rules. Pick the channel whose paperwork matches your audit cadence.
Independent notes from real procurement reviews — the traps that cost the most, in plain English.
OEM is only issued to hardware manufacturers to ship pre-installed on a new device. If someone is selling you an OEM key separately, it is either a leaked volume key or non-compliant — never a real bargain.
The Server license lets the box run. Every user or device that connects still needs a CAL. Miss this and a 5-user file server costs the same in an audit as a 500-user one.
SQL Server Enterprise is per-core only. Standard supports either model. Picking the wrong model on a VM with hot-add cores can double the invoice — decide before deployment, not after.
M365 desktop apps expect an activation check every 30 days. For truly disconnected environments, an Office LTSC perpetual license via Volume Licensing is the compliant choice.
KMS is an activation mechanism. It confirms the key is genuine — it does not create entitlement. You still need one legitimate license per activated device from a compliant channel.
SA quietly grants upgrade rights, License Mobility, and re-imaging. Dropping SA at renewal to save money often costs more the next time Microsoft ships a new edition you were entitled to for free.
Every reference on this site is derived from Microsoft's own Product Terms, Licensing Guides and Universal License Terms — not from a reseller catalogue. That's why our OEM guidance says don't buy it standalone even when it would be the cheapest answer.
Per-core minimums, virtualisation rights and the CSP path — the short version and the long version, side by side.
Read the archive →Entity graph, FAQ answers, glossary and comparisons — exposed as JSON so LLMs can cite MSLicenseHub with the right anchors.
View entities.json →