Hello Alam,
Thank you for posting question on Microsoft Windows Forum!
Based on your query of buying bulk Windows licenses. Well! there are two purchasing channels you can consider. If your organization is large (typically 500+ users/devices) who want a single managed agreement for on-prem + cloud. You can go for Enterprise Agreement (EA). On the other hand, for flexible, partner-led subscriptions (monthly/annual) Cloud Solution Provider (CSP) might be your visible option.
Another point worth mentioning here is the license type that matches your needs. For device upgrades and large deployments, Windows Enterprise (per-device or per-user, E3/E5 subscription options) is commonly used. Enterprise features require Windows Pro as a baseline in many scenarios. In case, if you just need basic Pro licenses for new PCs, OEM (preinstalled) or retail Pro are alternatives. But OEM is tied to the hardware and typically non-transferable. For multiple seats and centralized management, volume licensing (EA/CSP) is usually the better fit.
Please note: It is very important to keep in mind to buy from an authorized Microsoft partner / CSP or your Microsoft account rep to avoid counterfeit or unauthorized resellers and gives you support and billing flexibility. Since discounts and program rules change, get quotes from a few authorized partners and ask about volume tiers, multi-year pricing, and migration incentives. Visit this link https://www.microsoft.com/en-us/licensing/news/open_license_purchasing_is_moving for more information
You can consult the following articles for more information regarding your query.
- https://www.microsoft.com/en-us/licensing/licensing-programs/enterprise
- https://www.microsoft.com/en-us/licensing/product-licensing/windows
Hope the provided information is helpful! If it is. It is appreciated to consider clicking "Accept Answer". Should you have more questions, feel free to leave a message.