Microsoft SQL Server is licensed per Core, or server with Client Access Licenses (CALs). With both license options you always license the actual server, with only one exception what we will cover later. Microsoft offers two main editions of SQL server licenses.
Express Edition The entry-level, free database ideal for learning and building desktop and small server data-driven applications. Great for independent software vendors, developers, and hobbyists.
Developer Edition Includes all the functionality of the Enterprise edition but is licensed for development and testing only, not for production. Perfect for developers building and testing applications.
Web Edition A low total-cost-of-ownership option for web hosters and web VAPs, offering scalability, affordability, and manageability for web properties. Best for small to large-scale web applications.
Standard Edition Suitable for small to medium-sized businesses needing effective database management with minimal IT resources.
Enterprise Edition Ideal for mission-critical workloads and large-scale applications requiring high service levels and advanced analytics.
Count the Required Number of Core Licenses
SQL Server licensing can be calculated using two primary methods: Per Core Licensing with a minimum of 4 cores per CPU/VM or per Server + CAL Licensing.
Per Core Licensing
- SQL Server is licensed based on the total number of cores in the physical or virtual machine.
- A minimum of four cores is required per physical processor or virtual machine.
- This license model is recommended for environments with many users, as it does not require CALs.
Server + CAL Licensing
- A Server License is required for each server.
- CALs are required for each user or device accessing SQL Server.
- This model is cost-effective for smaller organizations with fewer users and devices or for very heavy machines with 20+ cores.
Licensing SQL Server in Non-Virtualized Environments
For non-virtualized environments, licensing SQL Server involves the following:
- Physical Core Licensing: Count all physical cores on the server and ensure a minimum of four core licenses per processor.
- Server + CAL Licensing: Purchase one Server License per server and CALs for each user or device.
To ensure accurate licensing, collect the following data:
- Server name
- SQL Server edition and version
- Server Role (since SQL server part of System Center is included in the Sys license)
- Number of processors and cores per processor
- Environment type (production, development, testing, etc.)
Licensing SQL Server in Virtualized Environments
Virtualized environments often require more detailed analysis. Licensing options include:
- Per Virtual Core Licensing
- Core licenses are required for each virtual core assigned to the SQL Server instance.
- A minimum of four core licenses is required per virtual machine.
- Unlimited Virtualization
- Requires licensing all physical cores on the host server with SQL Server Enterprise Edition.
- A minimum of four cores is required per physical processor.
- Active SA is required to unlock unlimited virtualization rights, allowing you to run an unlimited number of SQL Server instances on the licensed server.
To support calculations, collect:
- Host and cluster names
- Number of virtual machines and their virtual cores
- SQL Server editions and versions deployed
- Server Role (since SQL server part of System Center is included in the Sys license)
- Environment types: On-premises, cloud (e.g., Azure), or hybrid.
- Do I have Software Assurance on my licenses (for license mobility or unlimited virtualization)?
How to Calculate the Licenses
SQL Server / Client Access License (CAL) License Model
In the Server + CAL model:
- Each user or device accessing SQL Server must have a CAL.
- Analyze whether users use multiple devices or whether devices are shared among multiple users to determine the most cost-effective licensing strategy.
| VMs | #CPU | VM Configuration | CAL Requirements |
| 2 VMs | 4 vCPUs each (8 total) | 2 SQL Server licenses | 1 CAL per user or device accessing SQL Server. |
| 2 VMs | 8 vCPUs each (16 total) | 2 SQL Server licenses | 1 CAL per user or device accessing SQL Server. |
| 4 VMs | 4 vCPUs each (16 total) | 4 SQL Server licenses | 1 CAL per user or device accessing SQL Server. |
| 6 VMs | 4 vCPUs each (24 total) | 6 SQL Server licenses | 1 CAL per user or device accessing SQL Server. |
SQL Server Per Core License Model
In the per core model:
- Each Core needs to be licensed with a minimum of four cores per virtual machine.
| VMs | #CPU | VM Configuration | CAL Requirements |
| 2 VMs | 4 vCPUs each (8 total) | 8 Cores to license | – |
| 2 VMs | 8 vCPUs each (16 total) | 16 Cores to license | |
| 4 VMs | 4 vCPUs each (16 total) | 16 Cores to license | – |
| 6 VMs | 4 vCPUs each (24 total) | 24 Cores to license | – |
Licensing SQL Server in Azure
SQL Server can be licensed in Microsoft Azure through two main approaches:
- Bring Your Own License (BYOL)
- Available via Azure Hybrid Benefit.
- Allows you to apply your on-premises SQL Server licenses to Azure Virtual Machines.
| VMs | #CPU | VM Configuration | CAL Requirements |
| 2 VMs | 4 vCPUs each (8 total) | 8 Cores to license incl. SA | – |
| 2 VMs | 8 vCPUs each (16 total) | 16 Cores to license incl. SA | |
| 4 VMs | 4 vCPUs each (16 total) | 16 Cores to license incl. SA | – |
| 6 VMs | 4 vCPUs each (24 total) | 24 Cores to license incl. SA | – |
- Pay-As-You-Go (PAYG)
- SQL Server licensing is included in the hourly pricing for Azure SQL Server.
| VMs | #CPU | VM Configuration |
| 2 VMs | 4 vCPUs each (8 total) | SQL license included in Azure hourly billing for the VMs. |
| 2 VMs | 8 vCPUs each (16 total) | SQL license included in Azure hourly billing for the VMs. |
| 4 VMs | 4 vCPUs each (16 total) | SQL license included in Azure hourly billing for the VMs. |
| 6 VMs | 4 vCPUs each (24 total) | SQL license included in Azure hourly billing for the VMs. |
- SQL Managed Instances
- With SQL Server Enterprise including SA you will receive 4 cores while buying 1.
| Qualified License | Microsoft Azure Data Service1 | Ratio of Qualified Licenses to Azure vCores |
| SQL Server Enterprise (Core) | SQL Managed Instance enabled by Azure Arc – General Purpose | 1 Core License:4 vCores |
| SQL Managed Instance enabled by Azure Arc – Business Critical | 1 Core License:1 vCore | |
| Azure SQL Database (Elastic Pool and Single Database)/Azure SQL Managed Instance – General Purpose | 1 Core License:4 vCores | |
| Azure SQL Database (Elastic Pool and Single Database)/Azure SQL Managed Instance – Business Critical | 1 Core License:1 vCore | |
| Azure Data Factory SQL Server Integration Services (Enterprise) | 1 Core License:1 vCore | |
| Azure Data Factory SQL Server Integration Services (Standard) | 1 Core License:4 vCores | |
| SQL Server Enterprise Virtual Machines | 1 Core License2:1 vCPU | |
| SQL Server Standard Virtual Machines | 1 Core License:4 vCPUs | |
| SQL Server Standard (Core) | SQL Managed Instance enabled by Azure Arc – General Purpose | 1 Core License:1 vCore |
| SQL Managed Instance enabled by Azure Arc – Business Critical | 4 Core Licenses:1 vCore | |
| Azure SQL Database (Elastic Pool and Single Database)/Azure SQL Managed Instance – General Purpose | 1 Core License:1 vCore | |
| Azure SQL Database (Elastic Pool and Single Database)/Azure SQL Managed Instance – Business Critical | 4 Core Licenses:1 vCore | |
| Azure Data Factory SQL Server Integration Services (Standard) | 1 Core License: 1 vCore | |
| Azure Data Factory SQL Server Integration Services (Enterprise) | 4 Core Licenses:1 vCore | |
| SQL Server Standard Virtual Machines | 1 Core License2:1 vCPU | |
| SQL Server Enterprise Virtual Machines | 4 Core Licenses2:1 vCPU |
Microsoft Product Terms: https://www.microsoft.com/licensing/terms/en-US/productoffering/MicrosoftAzure/EAEAS
Software Assurance Benefits
Active Software Assurance (SA) provides several advantages:
- Version Upgrades: Access to the latest SQL Server versions.
- License Mobility: Rights to move licenses across servers or to third-party shared servers.
- Unlimited Virtualization: Allows for an unlimited number of SQL Server instances on a fully licensed host.
- Azure Hybrid Benefit: Cost savings when migrating workloads to Azure.
- Failover Rights: Secondary instances for disaster recovery without additional licenses.
- Disaster Recovery: All editions. See Fail-Over Rights section below for additional terms for SQL Server.
- Self Hosting
Contact us today at info@2-data.com to learn how we can simplify your SQL Server licensing process and ensure you’re fully compliant with Microsoft’s terms.
Take the first step toward efficient, hassle-free licensing!
