Windows 10/11 Enterprise: CSP Subscription vs Software Assurance
For an organization of 10 to 500 people, Windows Enterprise is almost always a per-user subscription now: Windows 10/11 Enterprise E3 or E5 through CSP, or the copy already inside Microsoft 365 E3, E5 and F3. Volume licensing with Software Assurance still exists, and it is still the right tool for devices nobody signs in to. This guide sets the two side by side: unit, channel, activation, term, what each includes, which bundles already carry Windows Enterprise, and the five questions that decide.
The short answer: per user through CSP, per device only for unattended machines
- You already own Microsoft 365 E3 or E5: Windows 10/11 Enterprise is inside the suite (service plan reference, Microsoft Learn, August 2026). Buy nothing; assign the license and let subscription activation step the device up from Pro.
- You run Microsoft 365 Business Premium: it carries Windows 10/11 Business, not Enterprise. Most organizations under 300 users never need more. Add Windows Enterprise E3 only for users who need an Enterprise-only feature, and only for those users.
- You need Windows Enterprise without the rest of Microsoft 365: Windows 10/11 Enterprise E3 in CSP, per user, monthly or annual term, activated by sign-in. It is $91.20 per user per year on an annual commitment, $7.60 per month (Microsoft list price, October 2026 price list); see the Windows 10/11 Enterprise E3 and E5 pages.
- You have kiosks, shared shop-floor PCs or lab machines with no named user: subscription activation requires per-user licensing and does not work with per-device licensing (Microsoft Learn, subscription activation). Those devices need a per-device Windows Enterprise upgrade with Software Assurance through a volume licensing agreement, or Windows VDA.
- You hold an Enterprise Agreement, MPSA or Open Value agreement with Software Assurance: keep the rights until the agreement ends, then move the users to CSP and keep volume licensing only for the unattended devices.
The reason the per-user model wins at this size is operational, not just financial: no keys, no KMS host, no true-up, and the upgrade follows the person across their devices.
What Windows Enterprise E3 in CSP is
Microsoft describes Windows Enterprise E3 in CSP as a per-user subscription for organizations from one user to hundreds, sold through Partner Center (Microsoft Learn, "Windows Enterprise E3 in CSP"). The mechanics, from the same page and the subscription activation documentation:
- Prerequisites: a currently supported version of Windows Pro installed and activated on the device, and Microsoft Entra ID for identity. Devices must be Microsoft Entra joined or hybrid joined; workgroup-joined or Entra-registered devices are not supported.
- Activation: when a user with the license signs in, the operating system steps up from Windows Pro to Windows Enterprise with no product key and no restart.
- Expiry: when the license is removed or the subscription lapses, the device reverts to Windows Pro after a grace period of up to 90 days.
- Clouds: available in commercial and GCC tenants since 1 October 2022; not in GCC High or DoD.
- What the SKU carries (service plan reference, August 2026): Windows 10/11 Enterprise, Universal Print, the Windows Update for Business deployment service and Windows Autopatch. Windows 10/11 Enterprise E5 adds Microsoft Defender for Endpoint.
On the October 2026 price list, Windows 10/11 Enterprise E3 is $91.20 per user per year ($7.60 per month) and Windows 10/11 Enterprise E5 is $153.60 per user per year ($12.80 per month), both on an annual commitment. Under the New Commerce Experience it is sold on a monthly or annual term with a seven-day cancellation window after purchase or renewal; how NCE terms work is covered separately.
What Software Assurance on Windows means in 2026
Volume licensing sells the Windows Enterprise upgrade per device, perpetual, with Software Assurance as the subscription layer above it. The programs that still take new orders are Open Value and Open Value Subscription, MPSA, and the Enterprise Agreement where Microsoft still offers it. Open License stopped taking orders after 31 December 2021, and Software Assurance on Open License products moves to Open Value at renewal (Redmond Channel Partner and Tech Data coverage of Microsoft's announcement, January 2021). If an Enterprise Agreement is approaching its end date, our EA transition advisory ($1,950 per project) maps it to CSP or the Microsoft Customer Agreement for Enterprise.
What Software Assurance gives a per-device Windows license is the Enterprise edition itself (the base is Pro bought with the hardware) and new version rights for the agreement term. Lose the Software Assurance and the device keeps the last version it was entitled to, with no further upgrades.
Activation on this path is the traditional one: KMS or Multiple Activation Keys from the Volume Licensing Service Center. That is the model to keep for machines with no primary user, and nothing else.
Side by side
| Windows 10/11 Enterprise E3 or E5 in CSP | Windows Enterprise upgrade with Software Assurance (volume licensing) | |
|---|---|---|
| Unit | Per user | Per device |
| Channel | CSP partner, Partner Center, New Commerce Experience | Open Value, MPSA or Enterprise Agreement |
| Term | Monthly or annual; seven-day cancellation window | Agreement term, typically three years |
| Base requirement | Windows Pro installed and activated; Entra joined or hybrid joined | Qualifying Windows Pro on the device |
| Activation | Subscription activation at sign-in; no keys | KMS or MAK |
| Included | Enterprise, Universal Print, Windows Update for Business deployment service, Windows Autopatch; E5 adds Defender for Endpoint | Enterprise upgrade and Software Assurance benefits |
| Devices with no named user | Not supported | Supported |
| At expiry | Device reverts to Pro after up to 90 days | Device keeps the last entitled version |
| Price | Quoted on request at Microsoft list price | Quoted on request through the agreement |
The row that decides most cases is "devices with no named user". Everything else favors the subscription for an organization that manages its users in Microsoft Entra ID.
The bundles that already carry Windows Enterprise
Before buying Windows Enterprise on its own, check what the suite licenses already include. Service plans from Microsoft's reference (August 2026); prices are Microsoft list price, October 2026 price list, per user per month on an annual term.
| Suite | Windows edition included | Also includes | Price |
|---|---|---|---|
| Microsoft 365 Business Premium | Windows 10/11 Business | Entra ID P1, Intune Plan 1, Defender for Business, Defender for Office 365 Plan 1, Autopatch features since April 2025 | $22.00 |
| Microsoft 365 E3 | Windows 10/11 Enterprise | Entra ID P1, Intune Plan 1, Defender for Endpoint Plan 1, Autopatch, Universal Print | $39.00 |
| Microsoft 365 E5 | Windows 10/11 Enterprise | Entra ID P2, Defender for Endpoint Plan 2 and the rest of the E5 security and compliance set | $60.00 |
| Microsoft 365 F3 | Windows 10/11 Enterprise for frontline workers | Frontline versions of the apps | $10.00 |
| Windows 10/11 Enterprise E3 | Windows 10/11 Enterprise | Universal Print, Windows Update for Business deployment service, Autopatch | Quoted on request |
Two related cases. Azure Virtual Desktop accepts Business Premium, Microsoft 365 E3, E5 and F3, Windows Enterprise E3 and E5, and Windows VDA per user as the eligible license for internal users (Microsoft Learn, AVD licensing). Windows 365 Business needs no Windows license in the tenant and stops at 300 users; Windows 365 Enterprise requires Windows Enterprise, Intune and Entra ID P1 per user, which Microsoft 365 E3 and E5 provide. The 2 vCPU, 8 GB, 128 GB Cloud PC is $32.40 per user per month on Business and $36.90 on Enterprise; the Windows 365 comparison covers the rest.
Windows 10 ESU: the per-device exception
Windows 10 support ended on 14 October 2025. Commercial Extended Security Updates run in three one-year blocks: year one to 13 October 2026, year two to 12 October 2027 and year three to 10 October 2028, bought per device per year through volume licensing or a CSP partner, and cumulative, so a device enrolled in year two pays for year one as well. The fee is not on the October 2026 price list and is quoted on request; the ESU calculator models it, and our ESU guide has the enrollment prerequisites.
ESU is the one case where a per-user Windows subscription does not settle the question, because the fee is per device regardless of how the user is licensed. The decision rule: a device that can run Windows 11 gets upgraded; a device that cannot gets ESU for the months until its replacement arrives, and no longer. The Windows 11 Migration and Windows 10 ESU Transition service is $25 per device plus a $1,950 tenant fee.
Five questions that decide
- Do users sign in with named Entra ID accounts on Entra-joined or hybrid-joined devices? Yes: per-user subscription. No: per-device volume licensing for those devices.
- Does the tenant already hold Microsoft 365 E3, E5 or F3 for the users in question? Yes: Windows Enterprise is already licensed; check assignment, not procurement. The Microsoft 365 License Audit and Optimization ($1,950 per project) finds the duplicates.
- Under 300 users and on Business Premium? Windows 10/11 Business covers them. Buy Windows Enterprise E3 for the handful who need an Enterprise-only capability, not for everyone.
- Any devices without a primary user? Count them. That count is your volume licensing order; the rest is CSP.
- Is an Enterprise Agreement, MPSA or Open Value agreement with Software Assurance expiring? Move the users to CSP at the end of the term, use the seven-day NCE window to correct quantities after the first order, and renew only the per-device lines.
Our Microsoft Volume Licensing consultation, free of charge for the review itself, maps an existing agreement to this list before the renewal date.
Frequently asked questions
Does Microsoft 365 Business Premium include Windows 11 Enterprise?
No. Business Premium includes Windows 10/11 Business. Windows 10/11 Enterprise is in Microsoft 365 E3, E5 and F3 and in the standalone Windows 10/11 Enterprise E3 and E5 subscriptions.
Can I still buy Windows through Open License?
No. Open License stopped taking orders after 31 December 2021. Perpetual Windows upgrades with Software Assurance are sold through Open Value, Open Value Subscription, MPSA or an Enterprise Agreement, and per-user subscriptions through CSP.
Do I need Software Assurance to run Windows 11 Enterprise?
No. A Windows 10/11 Enterprise E3 or E5 subscription, or Microsoft 365 E3, E5 or F3, steps a Windows Pro device up to Enterprise at sign-in. Software Assurance is the per-device route, needed for devices nobody signs in to.
What happens when a Windows Enterprise E3 subscription ends?
The device reverts to Windows Pro after a grace period of up to 90 days. Nothing is reinstalled; the Enterprise features switch off.
Does Windows Enterprise E3 include Windows Autopatch?
Yes. Microsoft's service plan reference lists Windows Autopatch, Universal Print and the Windows Update for Business deployment service in the Windows 10/11 Enterprise E3 SKU, and Microsoft's Autopatch prerequisites page also lists Business Premium and Microsoft 365 F3, E3 and E5 as eligible.
Can I use Windows Enterprise E3 for a shared kiosk PC?
No. Subscription activation requires per-user licensing and a signed-in licensed user, and Microsoft states it does not work with per-device licensing. License kiosks per device through volume licensing with Software Assurance.
How much does Windows 11 Enterprise E3 cost?
Windows 10/11 Enterprise E3 is $91.20 per user per year ($7.60 per month) on an annual commitment, Microsoft list price, October 2026 price list; E5 is $153.60 ($12.80 per month). Microsoft 365 E3, which includes it, is $39.00 per user per month on an annual term.
Sources
- Windows Enterprise E3 in CSP — Microsoft Learn; per-user model, prerequisites and activation confirmed through search excerpts on 2026-10-11, page not opened
- Windows subscription activation — Microsoft Learn; per-user requirement, join requirement, 90-day reversion and cloud availability confirmed through search excerpts on 2026-10-11, page not opened
- Product names and service plan identifiers for licensing — Microsoft Learn, ms.date 08/18/2026, checked 2026-10-11 (Windows 10/11 Enterprise E3 and E5, Microsoft 365 E3, E5 and Business Premium service plans)
- Windows Autopatch prerequisites — Microsoft Learn; eligible licenses confirmed through search excerpts on 2026-10-11, page not opened
- Licensing Azure Virtual Desktop — Microsoft Learn; eligible licenses confirmed through search excerpts on 2026-10-11, page not opened
- New commerce cancellation policy — Microsoft Learn; seven-day window confirmed through search excerpts on 2026-10-11, page not opened
- Microsoft Open License deadline — Redmond Channel Partner, 21 January 2021, and Microsoft ending its Open License program in 2022 — Tech Data; checked through search excerpts on 2026-10-11
- Microsoft commercial price list, October 2026: Microsoft 365 Business Premium, E3, E5 and F3, Windows 365 Business and Enterprise
Key takeaways
- For users who sign in to Entra-joined devices, Windows Enterprise is a per-user subscription: Windows 10/11 Enterprise E3 or E5 in CSP, or the copy inside Microsoft 365 E3 ($39.00), E5 ($60.00) and F3 ($10.00).
- Business Premium ($22.00) carries Windows 10/11 Business, not Enterprise; add Windows Enterprise E3 only for the users who need an Enterprise-only feature.
- Subscription activation needs Windows Pro on the device, Entra join or hybrid join and a licensed signed-in user, and the device reverts to Pro up to 90 days after the license goes.
- Per-device volume licensing with Software Assurance remains the right answer for kiosks, shared and lab machines that have no primary user.
- Open License took its last orders on 31 December 2021; Open Value, MPSA and the Enterprise Agreement are the remaining volume programs for per-device licenses.
- Windows 10 ESU is the per-device exception, running to 13 October 2026, 12 October 2027 and 10 October 2028 in cumulative yearly blocks, and is quoted on request.
Most tenants we audit are already paying for Windows Enterprise somewhere and buying it again elsewhere. The Microsoft 365 License Audit and Optimization ($1,950 per project, quoted in writing before work begins) lists every Windows entitlement you hold against every device that uses one; the Windows 11 Migration and Windows 10 ESU Transition service ($25 per device plus a $1,950 tenant fee) then moves the fleet. Subscriptions are at Microsoft's list price. Book a 30-minute call with your device count and your agreement end date.
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