CSP License Explained: Subscription, Perpetual License and Resale

Published October 23, 2026 · Updated October 23, 2026

A CSP license is a license bought through a partner in Microsoft's Cloud Solution Provider (CSP) program. CSP offers cloud services, software subscriptions and, since the end of the Open License program, perpetual server and Office software as well, handled through Partner Center under the Microsoft Customer Agreement. The decisive difference lies not in the program but in the form of the license: a subscription ends when the payments stop, a perpetual CSP license stays. This article explains what CSP is, what separates a subscription from a perpetual license in CSP, how CSP compares with Open Value and used licenses, and what applies to resale.

Contents

• What CSP is
• What CSP offers: cloud, subscription, perpetual license
• Subscription or perpetual license in CSP
• After Open License: CSP as the successor
• Software Assurance and License Mobility
• Pay-as-you-go through Azure Arc
• Resale: what EU law says about CSP licenses
• CSP, Open Value or used: the choice
• Frequently asked questions

What CSP is

CSP stands for Cloud Solution Provider. According to Microsoft's Partner Center, it is an authorization for partners to sell Microsoft products to customers, with two sales models: the indirect model, in which a partner buys through a distributor, and the direct-bill model, in which the partner bills directly with Microsoft. On its purchasing page, Microsoft describes CSP as a fully partner-managed solution: the partner advises, orders, manages and bills.

The contractual basis is the Microsoft Customer Agreement. Before a partner can order on a customer's behalf, the customer must accept this agreement; new customers cannot make a purchase until they do. According to Microsoft, the Microsoft Customer Agreement is available through CSP partners around the world and replaces the classic volume licensing agreement for these customers.

What CSP offers: cloud, subscription, perpetual license

Through CSP, partners sell, according to Microsoft, the full range of cloud services and various other offers, including server and perpetual software. For the software, fixed rules apply in Partner Center:

• Keys: partners see product keys and downloads in Partner Center (Admin agent role), customers in the Microsoft 365 admin center (Global admin role).
• Activation: CSP purchases are activated with a Multiple Activation Key (MAK); according to Microsoft, KMS keys are not available, even upon request. What this means for organizations with their own KMS host is explained in KMS activation and MAK keys explained.
• Downgrade: in CSP, Microsoft fulfills downgrade rights to previous versions, for most products under the n-1 or n-2 rule, meaning one or two versions back.
• Cancellation: a perpetual software purchase can be canceled within 30 days, not afterwards. A software subscription can be canceled with a prorated refund only within the first seven days of a term. After a cancellation, Microsoft revokes all related keys and download links.

Subscription or perpetual license in CSP

The same software is often available in CSP in both forms. The differences that matter for operations and the balance sheet:

For planning, the first row is the most important. A subscription suits workloads that come and go and organizations that prefer ongoing costs to a purchase. A perpetual license suits servers that run for many years; it belongs to the organization, even if the partner changes.

After Open License: CSP as the successor

Until 2021, the Open License program was the entry into volume licensing for small and medium-sized businesses. Microsoft ended purchases through Open License on December 31, 2021 and retired the program on January 1, 2022; since that day, commercial customers can no longer buy or renew through it. For the future, Microsoft named two routes: customers buy perpetual software without Software Assurance from qualified partners in the CSP program; for purchases with Software Assurance, Microsoft recommends Open Value. Perpetual Open License licenses already acquired remain usable with full rights, and according to Microsoft, existing Open License agreements can continue to activate tokens until the end of 2026.

The former portal, the Volume Licensing Service Center, was retired by Microsoft in April 2024; classic volume licenses have since been managed in the Microsoft 365 admin center. Which other programs exist and what makes a volume license is covered in What is a volume license?

Software Assurance and License Mobility

Software Assurance, Microsoft's additional coverage with rights such as new versions, is not available in CSP: the Product Terms state that Software Assurance benefits are not available to Microsoft Customer Agreement customers. That is the most important difference from Open Value and the Enterprise Agreement, and it explains why Microsoft keeps pointing to Open Value for purchases with Software Assurance.

Microsoft is making up part of this for subscriptions: since April 1, 2026, Windows Server and SQL Server subscriptions in CSP have License Mobility according to Partner Center, meaning benefits equivalent to Software Assurance in the classic programs. Perpetual CSP licenses expressly remain unchanged and do not gain License Mobility. Anyone who needs Software Assurance, for example for products such as Exchange Server Subscription Edition whose operation requires it, is in the wrong place with a perpetual CSP license; see Exchange 2019 end of life.

Pay-as-you-go through Azure Arc

Besides the CSP subscription and the perpetual license, there is a third route for Windows Server 2025: pay-as-you-go through Azure Arc, which Microsoft describes as an alternative to conventional perpetual licensing, billed through the Azure subscription according to use. The use rights are set out in the Product Terms. Microsoft names two limits: the license applies only to the device on which it is enabled and, unlike a perpetual license, gives no rights for virtual machines on the same server. The requirements and the CAL rule are in Windows Server 2025 licensing.

Resale: what EU law says about CSP licenses

The Microsoft Customer Agreement allows the transfer of licenses only for fully paid, perpetual licenses, and only to affiliates or to third parties in the course of a divestiture or merger. The rules for all license types are in Transferring a Microsoft license. In the EU, the exhaustion principle applies alongside, and it takes precedence. In case C-128/11, the Court of Justice of the European Union ruled that the transfer of a program copy together with a license agreement granting a perpetual right of use for a fee is a first sale within the meaning of Article 4(2) of Directive 2009/24/EC, and that the rights holder can then no longer oppose the resale, regardless of any contract terms to the contrary. The previous owner must make their own copy unusable.

For CSP this means: a perpetual CSP license that has been paid in full meets the criteria the Court names and may be resold in the EU. A CSP subscription does not meet them, because the right of use is time-limited; the Court also expressly excludes separable service contracts such as maintenance agreements from exhaustion. When buying a used CSP license, the same three documents count as for any used license: proof of first sale in the European Economic Area (EEA), the previous owner's declaration and an unbroken chain of ownership. The framework is explained in Is used software legal?

CSP, Open Value or used: the choice

The rows are not mutually exclusive. Many organizations buy Microsoft 365 through a CSP partner and license their servers with used perpetual licenses, because choice of version, downgrade rights and ownership count there.

Frequently asked questions

What does CSP stand for?

Cloud Solution Provider, Microsoft's partner program for selling cloud services, software subscriptions and perpetual software through partners, based on the Microsoft Customer Agreement.

What is a CSP license?

A license bought through a CSP partner, as a subscription or as a perpetual license. Keys and downloads come from Partner Center or the Microsoft 365 admin center, and activation uses a MAK.

Is Windows Server available as a perpetual license in CSP?

Yes. Microsoft sells server and perpetual software through CSP; after the end of Open License, CSP is the route Microsoft names for perpetual software without Software Assurance.

Do I get a KMS key in CSP?

No. According to Microsoft, CSP purchases are activated with a MAK; KMS keys are not available, even upon request.

Can I resell a perpetual CSP license?

Under EU law, yes, if it is perpetual and paid in full: the Court of Justice of the European Union treats supply for a fee with a perpetual right of use as a first sale that exhausts the distribution right. A subscription cannot be resold.

What is the difference between CSP and Open Value?

Open Value is a classic volume licensing agreement with Software Assurance; CSP has no Software Assurance benefits but offers subscriptions, cloud services and perpetual software under the Microsoft Customer Agreement.

Are inexpensive Office or server licenses from the secondary market legal?

Yes, if they are perpetual licenses that were first sold in the EU or EEA with the rights holder's consent, and if the seller documents the first sale, the previous owner's declaration and the chain of ownership. If these documents are missing or the licenses are subscriptions, caution is advised.

What happens if I cancel a CSP subscription?

Within the first seven days of a term you receive a prorated refund. After a cancellation, Microsoft revokes the keys and download links, and the software may no longer be used.

What Lizenzus does for you

We supply used perpetual Microsoft licenses from volume licensing agreements, each with proof of first sale in the EEA, the previous owner's declaration and the chain of ownership; we do not supply CSP subscriptions or cloud services. The overview is at Buy Microsoft licenses. In your quote request, tell us which servers and access you want to license permanently; we tell you which versions are available. Your quote request is non-binding.

Sources

• Microsoft Learn: Cloud Solution Provider program overview, accessed October 23, 2026
• Microsoft Learn: Sell on-premises software through CSP, accessed October 23, 2026
• Microsoft Learn: Software subscriptions and perpetual software in CSP, accessed October 23, 2026
• Microsoft Learn: Confirm customer acceptance of the Microsoft Customer Agreement, accessed October 23, 2026
• Microsoft Learn: Partner Center announcements, April 2026, accessed October 23, 2026
• Microsoft Learn: Manage volume licensing agreements, accessed October 23, 2026
• Microsoft Learn: Volume Licensing Central, latest news, accessed October 23, 2026
• Microsoft Learn: Windows Server pay-as-you-go, accessed October 23, 2026
• Microsoft Licensing: Product Terms, Software Assurance Benefits, accessed October 23, 2026
• Microsoft Licensing: Microsoft Open License program changes and Open License purchasing is moving, accessed October 23, 2026
• Microsoft Licensing: Microsoft Customer Agreement and How to buy, accessed October 23, 2026
• Microsoft: Microsoft Customer Agreement, section License transfers, accessed October 23, 2026
• Official Journal of the EU: Directive 2009/24/EC, Article 4(2)
• Court of Justice of the EU, judgment of July 3, 2012, C-128/11 UsedSoft, paragraphs 48, 70 and 77 and the operative part