Hi @Sam Chen,
Thank you for reaching out to the SQL Forum.
Microsoft allows mixed licensing models (perpetual and subscription) within the same SQL Server edition and version, provided that all cores are properly licensed and compliance is maintained. Here's how it works:
- Allowed: You can combine perpetual licenses (e.g. from a Volume Licensing agreement) with subscription licenses (from CSP or SPLA) as long as they cover the same edition and version of SQL Server.
- Core Licensing Rule: Every physical or virtual core must be licensed. You can use 4 cores of perpetual and add 2 or more cores via subscription, but you must ensure the total number of cores is covered.
- Same Edition Required: You cannot mix SQL Server Standard (perpetual) with SQL Server Enterprise (subscription), or vice versa.
- Same Version Recommended: Mixing SQL Server 2022 perpetual with SQL Server 2025 subscription may cause support and compliance issues. Stick to the same version unless you're upgrading all cores.
Thanks,
Lakshmi.