Increase partition size

Change and increase partition size on Windows Server 2019?

The disk drives for Operating System, backup, database, exchange and projects will become full after running the server for a period of time. In this situation, you can change partition size without recreating drives and restoring. As long as there are free space in any other drives, you can decrease them and increase size of the partition that is running out of space.

In this article, I’ll show you how to change and increase partition size in Windows Server 2019 without losing data.

Increase partition size

Change partition size with Disk Management

Windows Server 2019 has built-in Disk Management tool to change partition size. Shrink Volume feature can decrease partition size and release free space. Extend Volume feature can increase partition size when there is adjacent Unallocated space on the right side. However, these two functionalities only work in this condition.

Before extending a volume, you must decrease another drive. When you shrinking drive D with Shrink Volume, Unallocated space can only be produced on the right side, but to increase C drive with Extend Volume, there must be Unallocated space on the left side of drive D. The only option to get adjacent Unallocated space behind C drive is by deleting D, but who can do this, as all programs and some Windows services are running from it.

That means, to decrease and increase partition size in Windows Server 2019, you need server partitioning software in most cases.

Change partition size with Partition Editor

Comparing with Windows native Disk Management, NIUBI Partition Editor has advantages such as:

  • When shrinking a drive, NIUBI can generate Unallocated space on either side.
  • When extending a drive, Unallocated space on either side can be used.
  • NIUBI can move partitions, so you can increase partition size by shrinking nonadjacent volumes.
  • Disk Management Shrink and Extend Volume feature only supports NTFS partition, but NIUBI supports both NTFS and FAT32 partitions.
  • Besides changing partition size, NIUBI Partition Editor can do much more disk and partition management operations.

When resizing and moving partitions, you just need to drag and drop on the disk map of NIUBI. It is very easy to use, even if you have no experience of using such kind of software.

How to decrease partition size

Download NIUBI Partition Editor and you’ll see all disk partitions that connected to this server. In my test server, there are 3 system reserved partitions and drive C, D, E in same Disk 0. Both drive D and E have plenty of free space, so I can decrease them to increase C drive space.

NIUBI Main window

Right click drive D and select Resize/Move Volume. In the pop-up window, drag left border rightwards.

Shrink drive D

Drive D is shrank and 20GB Unallocated space is generated on the left side. (If you drag the right border leftwards, Unallocated space will be produced on the right side.)

Drive D shrank

How to increase partition size

Right click drive C and select “Resize/Move Volume”, drag the right border rightwards to combine the Unallocated space in the pop-up window.

Extend C drive

C drive size is increased to 59.40GB.

C drive extended


  • The operations you do won’t be executed immediately, they’ll be listed as pending on bottom left. You can cancel the unwanted operations by clicking Undo or click Apply on top left to execute.
  • NIUBI Partition Editor has Hot Resize technology to change partition size without rebooting. The operations with  can be done in Windows without interruption.

Watch the video how to decrease and increase partition size on Windows Server 2019:

In Summary

To change partition size in Windows Server 2019, Disk Management is useless in most cases. Run NIUBI Partition Editor and drag either border to decrease partition size, or increase partition size by merging Unallocated space. You just need 1 more step to move partition if the Unallocated space is nonadjacent.

Download to try