How to merge 2 unallocated space

by John, Published on: October 3, 2020

This article introduces how to merge two Unallocated partitions without losing data on hard drive.

Applies to: Windows 10, Windows 8, Windows 7, Windows Vista, Windows XP, Windows Server 2019, Windows Server 2016, Windows Server 2012 (R2), Small Business Server 2011, Windows Server 2008 (R2) and Windows Server 2003 (R2).

Unallocated space is kind of disk space that is not allocated to any partition. In Windows XP and Server 2003 native Disk Management, you can get Unallocated space by deleting a partition, Unallocated space can only be used to create new volume. In Windows 7, Server 2008 and all subsequent versions, you can get Unallocated space by either deleting or shrinking a partition. Unallocated space can be used to either create new volume or extend an allocated partition. However, Disk Management has 3 major shortage:

  1. It can only merge Unallocated space to the contiguous partition on the left and on the same disk.
  2. It cannot merge two Unallocated space on a disk.
  3. It cannot move the location of Unallocated space.

Cannot merge 2 Unallocated space in Disk Management

In Windows XP and Server 2003 Disk Management, you cannot shrink, extend or move partition. Even in Windows 7 and subsequent versions, there's no merge function. If you want to merge Unallocated space to a partition, you have to run Extend Volume. As I said above, Disk Management can only merge Unallocated space to its contiguous partition on the left. It cannot merge Unallocated space to the right contiguous or any non adjacent partition. It cannot move Unallocated space or merge 2 Unallocated partitions together.

Extend Volume greyed out

As you see in the screenshot of my computer:

There is no Merge Volume function when clicking any partition. Extend Volume is only activated to D drive, because it is on the left of this Unallocated space.

If you want to merge two Unallocated space, you must run third party software to move partition towards left or right.

How to merge two Unallocated partitions on a disk

Download NIUBI Partition Editor, you'll see the main window with disk partition structure and other information. As you see in my computer, there is 10GB Unallocated space on the left of D drive, and there's another 10GB Unallocated on the right.

To merge these 2 Unallocated space, you just to move D: drive location. Right click it and select "Resize/Move Volume, you have two choices in the pop-up window.

Drag the middle towards right, then you can merge 2 Unallocated partitions on the left of D.

Drag the middle towards left, then you can merge 2 Unallocated partitions on the right of D.

How to merge two Unallocated partitions in Windows 10/8/7/Vista/XP and Server 2019/2016/2012/2008/2003:

Video guide

It is very easy to merge two Unallocated space on a disk, but it doesn't mean any tool can accomplish this task well. All files in the partition that between these 2 Unallocated space must be moved to new locations. In addition, the parameters of associated partitions must be modified. Any slight error leads to partition damage and data lose.

Better than other tools, NIUBI Partition Editor has advanced Virtual Mode, 1-Second Rollback and Cancel-at-well technologies to protect system and data. It is 30% to 300% faster because of the unique file-moving algorithm. Besides shrinking and extending partition, moving and merging Unallocated space, it helps you do many other operations.

Download

Can't merge 2 Unallocated partitions on different disk

If the Unallocated partitions are on different disk, no software can merge them together, no matter you use physical hard disk or virtual machine. To physical disk, the size is fixed, you cannot add more Unallocated space to it. To virtual machine disk, you can expand it but you still cannot move Unallocated space from another disk.