SQL Server Express allows the maximum of 10GB/10240MB for a database size.

I have a database which currently is ~8000 MB in size. The unallocated space is ~7000 MB.

The question is: how many megabytes are available for growth/storing data on this database from that moment on?

Is it ~2000MB or ~9000MB?

What will happen if the database .mdf file reaches the maximum of 10240MB while the unallocated space is still around 7-8 000 MB?

Will it prevent new records in the database from that moment on, or it will start using the unallocated space?


  • Autogrowth is by 50MB and the maxsize is unlimited.
    – silverbackbg
    Commented Nov 30, 2020 at 21:06

1 Answer 1


I haven't used SQL Express personally but from my understanding of how Microsoft's licensing works you'll be able to grow to the 10 GB limit, but then if the file tries to grow any further the operation will fail.

The limit is the allocated size of the MDF file. So technically you have about 2 GB left. Once your MDF is 10 GB, even if not all of that space is used, you're at the limit per the licensing agreement. You should still be able to use the server and fill the unused allocated space up though (without incurring any further file growths) and still be compliant.