VLSC and VLMS Administration: Complete Guide for Enterprise Licensing Teams

Microsoft's Volume Licensing Service Centre (VLSC) and its successor the Volume Licensing Management Service (VLMS) together hold the master record of your organisation's perpetual licence entitlements, Software Assurance benefits, and product keys. Yet 60% of the IT asset managers we work with have never been properly trained on either system — they learned by trial and error, and they're missing entitlements worth thousands of pounds per year as a result. This guide closes that gap with the operational detail that Microsoft's own documentation omits.

VLSC vs. VLMS vs. Microsoft Admin Centre: Knowing Which System Holds What

Before you can administer your Microsoft licensing estate effectively, you need to understand which portal holds which data. Microsoft has fragmented its licensing management across three primary systems, and each covers a different slice of your entitlements.

System	What It Contains	Primary Users	Access URL
VLSC (legacy)	Perpetual licences pre-2022; SA-covered products; product keys; historic true-up records; on-premises software downloads	IT Asset Managers, Software Licence Administrators	www.microsoft.com/licensing/servicecenter
Microsoft Admin Centre	M365 subscriptions; Teams; Azure AD; Intune; cloud service entitlements; user assignment management	IT Admins, M365 Global Admins	admin.microsoft.com
Azure EA Portal	Azure spend commitments; MACC drawdown; department/account hierarchy; Azure reservation management	EA Billing Admins, FinOps teams	ea.azure.com
Microsoft Partner Centre	CSP-acquired subscriptions; partner-managed licences	CSP reseller contacts, IT procurement	partner.microsoft.com

The VLSC migration to Microsoft 365 Admin Centre is ongoing but not complete. As of 2026, organisations with EAs signed before January 2022 continue to access perpetual and SA entitlements via VLSC. New EA enrollments increasingly surface in Microsoft 365 Admin Centre. The transition is product-by-product, not agreement-by-agreement — meaning most enterprise organisations must administer both systems simultaneously for the foreseeable future.

VLSC Account Structure and Role Management

VLSC access is organised around agreements, not individuals. Understanding the role hierarchy is critical because a missing role assignment is the most common reason licensing teams cannot access the entitlements they have purchased.

VLSC Role Hierarchy

Role	Permissions	Who Should Hold It	How to Assign
Agreement Administrator	Full access: entitlements, keys, downloads, contacts management, true-up reporting	IT Asset Manager / SAM programme owner	Assigned by Microsoft at EA signature; can be transferred via Microsoft Support
Download Access	Software downloads and product keys only — no entitlement viewing, no contact management	IT deployment teams needing software access	Administrator grants via Manage Contacts
Online Service Administrator	Manages M365 subscriptions and cloud services within VLSC (legacy cloud view)	Cloud administrator	Administrator grants via Manage Contacts
Reporting	View-only access to licence summaries and true-up reports	Finance, procurement, compliance teams	Administrator grants via Manage Contacts

Managing Multiple Agreement Numbers

Large organisations often carry multiple agreement numbers in VLSC: the primary EA, separate Open Value agreements for smaller entities, Select Plus remnants from pre-EA licensing, and possibly affiliate agreements. Each agreement number must be individually linked to your VLSC account. Unlinked agreements are invisible in VLSC — their entitlements do not appear in summary views, their SA benefits cannot be activated, and their product keys cannot be retrieved.

To check whether all your agreements are linked, navigate to VLSC > Subscriptions > Licences. The list should match your internal record of all Microsoft agreement numbers. Any discrepancy indicates an unlinked agreement. Request a link by contacting your Microsoft account manager with the agreement number and proof of authorisation (typically the countersigned agreement or a purchase order).

Entitlement Management in VLSC

VLSC's entitlement data is the authoritative record of what you have purchased and are entitled to deploy. Understanding how to read and export this data is foundational to licence reconciliation and audit readiness.

Reading the VLSC Licence Summary

Navigate to VLSC > Licences > Summary to see the consolidated entitlement view. Key columns to understand:

• Product Pool: Applications, Systems, Servers — organises licences into Microsoft's billing pools. This matters for true-up calculations where each pool is reported separately.
• Licence Type: SA, Perpetual SA, Upgrade SA — indicates whether Software Assurance is active. "SA" means current. "Perpetual SA" means SA has lapsed but the perpetual licence is retained. "Upgrade SA" means the licence was acquired as an upgrade, not a full licence.
• Effective Quantity: The number you can legally deploy. This may differ from purchased quantity where licence mobility provisions, multi-use rights, or downgrade rights apply.
• Version Coverage: The product versions you are entitled to deploy under current SA. Click any product row to see version-specific entitlements.

Software Assurance Benefit Activation

SA benefits are not automatically active — they must be individually activated in VLSC. This is one of the most common sources of value leakage in Microsoft estates. SA benefits that require manual activation include: Home Use Programme, E-Learning, Training Vouchers, Spread Payments, Step-Up Licences, and Windows Virtual Desktop rights.

Our data across 500+ EA engagements shows that 34% of organisations have never activated their SA Training Voucher benefits, and 29% have unactivated Step-Up Licence rights worth an average of $18,000 per organisation. For the full list of SA benefits and their commercial value, see the Software Assurance complete guide.

Product Keys and Software Downloads

VLSC is the source of truth for product keys for all on-premises Microsoft software acquired under volume agreements. Understanding key types and activation limits prevents deployment failures and compliance gaps.

MAK vs. KMS Keys

Microsoft provides two key types for most on-premises products. MAK (Multiple Activation Key) keys activate directly against Microsoft's activation servers and have a fixed activation limit — typically 10× your purchased quantity, capped at 4,000 activations per key. KMS (Key Management Service) keys activate clients against an internal KMS server you deploy and manage, with no activation limit.

For deployments over 25 instances, KMS is strongly preferred. It eliminates MAK ceiling risk and works in air-gapped environments (once the KMS server has been activated). MAK keys are appropriate for individual machines, development environments, and environments that cannot reach a KMS server.

Retrieving Product Keys Correctly

VLSC lists keys under Products & Downloads > Product Keys. Keys are listed by product, not by agreement — if you have the same product under multiple agreements, you may see multiple key entries. Always use the key associated with the agreement covering the version you are deploying. Using a key from a different agreement version than your entitlement creates a version-coverage discrepancy in your SAM data.

Download the product itself from Products & Downloads > Downloads. Select the exact version, language, and architecture matching your deployment requirements. VLSC retains download access to all versions covered during your SA period — even if SA has subsequently lapsed — provided you download within 12 months of SA expiry.

True-Up Reporting via VLSC

Enterprise Agreement true-ups are submitted via VLSC under Subscriptions > True-up Submission. The annual true-up process requires submitting actual deployment counts for all products covered under the EA, triggering additional licence charges for quantities deployed above the EA baseline.

True-Up Reporting Workflow

1. Export current entitlements: Download the licence summary from VLSC as an Excel file 60 days before your anniversary date.
2. Run discovery and reconciliation: Use your SAM tool to produce current deployment counts by product and version. For complex environments, see the reconciliation automation guide.
3. Identify delta: Compare deployed quantities against EA baseline. Products above baseline require true-up payment. Products below baseline represent potential EA restructuring opportunities at renewal.
4. Submit via VLSC: Enter quantities in the true-up submission form. Microsoft processes the submission and issues a price quote for additional licences within 5–10 business days.
5. Review and challenge: The quote is not automatically binding. You have 30 days to challenge pricing, request volume tier recalculations, or apply promotional offers before the invoice is issued.

VLSC Data Exports and SAM Integration

VLSC licence data must feed into your SAM platform for full reconciliation coverage. The export format and frequency matter for data quality.

VLSC Export Best Practices

Export formats: VLSC offers Excel (.xlsx) and XML exports for licence data. SAM tools (Snow Software, Flexera) have pre-built VLSC connectors that import the XML export directly. Always use the XML format for SAM tool imports — it preserves product identifiers needed for SKU normalisation. The Excel format is human-readable but loses some product code precision.

Export cadence: Pull VLSC data monthly as minimum. Quarterly is insufficient because VLSC reflects purchase-order processed dates, and new purchases can appear weeks after order placement. Monthly exports ensure your SAM tool's entitlement base stays within 30 days of actual entitlements.

For context on how VLSC data integrates into the broader SAM programme framework, and for the full SAM tool comparison covering VLSC connector quality, see those dedicated guides.

Common VLSC Administration Mistakes

Mistake	Frequency	Business Impact	Prevention
Single VLSC administrator	Very common (38%)	15–30 day access loss when admin leaves	Maintain minimum 2 administrators; document in succession plan
SA benefits never activated	Common (34%)	$18K average unused value per org	Annual SA benefit audit; activate Training Vouchers, Home Use, Step-Up
Unlinked agreement numbers	Common (27%)	Invisible entitlements; reconciliation gaps	Quarterly agreement audit against internal PO records
MAK key exhaustion	Moderate (15%)	Deployment failures; emergency Microsoft Support case	Monitor MAK activation counts; switch to KMS for >25 instances
Wrong product version downloaded	Moderate (19%)	Version coverage compliance gap	Cross-reference SA coverage dates before download selection
True-up submission errors	Common (31%)	Incorrect billing; potential under-reporting liability	Independent reconciliation review before submission; 30-day challenge window use

Preparing for the VLSC-to-Admin-Centre Migration

Microsoft is progressively migrating volume licensing administration from VLSC to Microsoft 365 Admin Centre. The timeline is product-by-product and agreement type-by-agreement type. Organisations should prepare for the migration without waiting for it to be forced upon them.

Key preparation steps: Ensure all VLSC administrators have Microsoft Entra ID accounts (not legacy Microsoft Accounts where possible), as Admin Centre uses Entra ID authentication. Document all current VLSC configurations including agreement links, contact assignments, and activated SA benefits — these may not migrate automatically. Establish a parallel Admin Centre administrator structure before migration, not after.

The migration does not affect perpetual licence entitlements — these transfer to the new portal intact. SA benefits may require re-activation in the new portal. Product keys for legacy on-premises products remain accessible in VLSC even after migration for cloud products, as Microsoft maintains VLSC as a legacy portal for perpetual licence management.

Frequently Asked Questions

What is the difference between VLSC and VLMS?

VLSC (Volume Licensing Service Centre) is Microsoft's older portal for managing perpetual and Software Assurance licences, downloading software, and retrieving product keys. VLMS (Volume Licensing Management Service) is the newer Microsoft Admin Centre experience replacing VLSC for new agreement types. Both remain active simultaneously — existing perpetual licences and SA-covered products remain in VLSC while new cloud-first agreements move to Microsoft Admin Centre. Organisations with EAs signed before 2022 typically access both systems.

How do I add an administrator to VLSC?

Navigate to VLSC > Subscriptions > Manage Contacts. Select the agreement and click Add Contacts. Enter the new administrator's Microsoft Account email, assign the role, and send the invitation. New administrators must accept within 30 days.

What happens to VLSC when my Software Assurance expires?

When SA expires, you retain access to VLSC for downloading software versions covered during the active SA period, retrieving product keys, and viewing historic entitlement records. Your perpetual licence entitlements remain permanently in VLSC regardless of SA status — they do not expire.

Why can't I see all my licences in VLSC?

Three common causes: (1) Multiple agreement numbers under different contacts — your account may only be linked to some agreements. (2) Cloud subscriptions (M365, Azure) are in Microsoft Admin Centre, not VLSC. (3) CSP-acquired licences are in your CSP provider's portal. Consolidating your entitlement view requires pulling data from all three sources simultaneously.

How long does it take for a new EA purchase to appear in VLSC?

Typically 3–5 business days after Microsoft processes the order. During true-up periods, processing can take 7–14 business days. If a purchase does not appear after 15 business days, open a support case via VLSC > Support with the purchase order number and Microsoft agreement number.

What is a VLSC Product Key and how many activations do I get?

VLSC provides MAK (Multiple Activation Key) and KMS (Key Management Service) keys. MAK keys have a fixed activation limit of approximately 10× purchased quantity. KMS keys have no activation limit and are preferred for deployments over 25 instances.