Windows Server Licensing on Raff: Evaluation, SPLA, BYOL

Why Windows licensing on a cloud server is its own topic

Linux is straightforward — install, run, ship. Windows Server is licensed software, and how you license it determines your monthly cost, your audit posture, and what you can legally do with multi-user RDP, SQL Server, or Office.

On Raff there are three legitimate paths to a licensed Windows Cloud Server, and we walk through each one below. None of them require a phone call to Microsoft.

The three license paths on Raff

Path	Best for	What you pay	Production-ready?
6-month evaluation	Testing, dev, learning	Included with every Cloud Server	No (non-production only)
SPLA — we provide	Most production use	Monthly, no commitment	Yes
BYOL — your license	Existing Microsoft customer with eligible licenses	Already paid Microsoft directly	Yes (with caveats — see below)

Path 1: 6-month evaluation (free, non-production)

Every Raff Windows Cloud Server ships with the Microsoft 180-day evaluation edition of Windows Server 2019, 2022, or 2025. It's the full Standard or Datacenter binary — no feature reductions.

The fine print:

Microsoft caps it at 180 days. After that it shuts down hourly until you license it.
You can run slmgr /rearm up to 6 times, which can extend the evaluation up to roughly 3 years for non-production. (Source: Microsoft Q&A on rearm limits.)
It is not licensed for production workloads. Use it for proofs-of-concept, dev environments, lab work, training. If real business depends on it, move to SPLA or BYOL.

Path 2: SPLA — Raff provides the license (monthly)

Microsoft's Service Provider License Agreement (SPLA) is the program built specifically for hosting providers. We're a SPLA partner, so we can license Windows Server (and SQL Server, and several other products) to you on a monthly basis with no commitment.

What you get with a SPLA license on Raff:

Monthly billing. No 3-year commitment, no upfront capital.
No Windows Server CALs required. When Windows Server is licensed via SPLA, the CAL requirement is replaced by the Subscriber Access License built into the per-core fee. (Source: Microsoft SPLA Licensing Guidance.)
Genuine Microsoft licensing. Activates against Microsoft, passes a Microsoft license audit.
Cancel anytime. Stop the Cloud Server, the license stops billing.

Why SPLA matters more in 2026: Effective September 30, 2025, Microsoft restricted SPLA on the "Listed Providers" — Azure, AWS, Google Cloud, Alibaba. You can no longer bring your own SPLA license to those clouds. Raff is not a Listed Provider, so SPLA still works here exactly as designed. (Source: Octopus Cloud — 2026 SPLA guide.)

Path 3: BYOL — bring your own license

If your company already owns Windows Server licenses, you can use them on Raff under Microsoft's License Mobility through Software Assurance rules. This is a real, supported option, but it has hard requirements:

The licenses must have active Software Assurance at the time of mobility.
You must submit a License Mobility verification form to Microsoft within 10 days of deployment.
Per-core licensing rules still apply: minimum 8 core licenses per VM, and the per-VM licensing option is only available with subscription or active SA. (Source: Microsoft Windows Server 2025 Licensing Guidance.)

What is BYOL-eligible:

Windows Server Standard / Datacenter (with SA + License Mobility)
SQL Server Standard / Enterprise (with SA + License Mobility)
Visual Studio subscriptions (for dev cloud servers only)

What is NOT BYOL-eligible to a hosting provider:

Office (Office Pro Plus, Office Home & Business) — must use Microsoft 365 Apps with SCA instead (see below)
Windows Server CALs purchased without SA
OEM-only licenses

If you're not sure whether your licenses qualify, send your purchase docs to support and we'll tell you straight — and if BYOL doesn't fit, switch to SPLA without redeploying the cloud server.

Per-core minimum — the gotcha

Microsoft licenses Windows Server per physical core, with a minimum of 8 cores per processor and 16 cores per server. (Source: Microsoft Licensing Guidance.)

In a hosted cloud server world this matters less because we license at the host level via SPLA — you don't see the per-core math on your invoice. But if you're calculating BYOL costs and your cloud server only has 4 vCPU, don't assume you only need 4 core licenses. The minimum is 16 if you're licensing the underlying server, or 8 per VM under the per-VM licensing option. Plan for the minimums.

RDS CALs — multi-user RDP

The 6-month evaluation, SPLA, and BYOL all give you 2 admin RDP sessions for free. The moment you want more than 2 users connecting via Remote Desktop simultaneously, you need RDS CALs (Per-User or Per-Device).

This is its own topic with real cost implications. Read the full guide: RDS CAL Licensing on Windows Server: Per-User vs Per-Device, BYOL vs SPLA.

SQL Server licensing — brief version

SQL Server Express is free and unlicensed — fine for small workloads (up to 10 GB databases, 1 GB RAM, 1 socket / 4 cores per instance).

For Standard or Enterprise, you have the same three paths as Windows Server: BYOL with License Mobility (must have SA), SPLA monthly via Raff, or a SQL Server developer license (free, non-production only). The per-core minimum is 4 core licenses per database server for SQL Server.

Microsoft 365 Apps (Office) — you need SCA

This is the section that catches the most customers off-guard.

You cannot install retail Office Home & Business or Office Pro Plus on a Windows Cloud Server that multiple users RDP into. Microsoft's licensing terms prohibit it. The supported path is Microsoft 365 Apps with Shared Computer Activation (SCA).

Plans that include SCA support (source):

Microsoft 365 Apps for enterprise (Office 365 E3, E5, A3, A5)
Microsoft 365 Business Premium
Project Plan 3 / Visio Plan 2 (for those apps specifically)

Plans that do NOT support SCA — common mistakes:

Microsoft 365 Business Basic
Microsoft 365 Business Standard
Office for Mac

Support cutoff dates to know:

Microsoft 365 Apps on Windows Server 2016 / 2019: support ended October 2025
Microsoft 365 Apps on Windows Server 2022: support ends October 2026
Microsoft 365 Apps on Windows Server 2025: full support

If you need Office on a Raff Windows Cloud Server, deploy it with the Office Deployment Tool and the SharedComputerLicensing flag set to 1. Each user signs in with their own Microsoft 365 account — the per-user license is what activates Office, not the cloud server itself.

What does NOT apply on Raff (so you stop wondering)

Azure Hybrid Benefit. This is an Azure-only program that lets you apply Windows Server / SQL Server licenses with SA to Azure VMs at a discount. It does not apply to third-party clouds. If you have AHB licenses, you can still use them on Raff via standard License Mobility — the discount mechanism is just different.

Windows 10 / 11 Pro on a server. Don't. The desktop SKUs are not licensed for server hosting. Use Windows Server Standard or Datacenter.

OEM licenses. OEM Windows Server licenses are tied to the original physical server they were sold with. They can't be moved to a cloud server, ever.

Audit posture

Raff is a Microsoft SPLA partner with monthly true-up reporting to Microsoft. Every cloud server we license under SPLA is reported, paid for, and activates against genuine Microsoft. If you're audited by Microsoft (or by your own customers' compliance team), we provide license attestation letters on request — no charge.

For BYOL deployments, you remain the licensee of record. We document the deployment in your account, and if Microsoft asks where the license is running, we confirm.

How to choose — quick decision tree

Just testing or learning? → Use the 6-month evaluation. Don't pay anything.
You already own Windows Server licenses with active Software Assurance? → BYOL via License Mobility. We help with the verification form.
Anything else (production, no existing licenses, want zero commitment)? → SPLA. Monthly billing, we manage it, no CAL math.

Ready to deploy?

Pick a Windows Cloud Server plan and you'll get the 6-month evaluation by default. When you're ready to license for production, message support and we'll switch you to SPLA on the same cloud server — no rebuild needed.

For multi-user RDP, read RDS CAL Licensing on Windows Server before you size your plan.

Windows Server Licensing on Raff: Evaluation, SPLA, and BYOL Explained