By Emily / Last Updated August 18, 2020

What is an unallocated partition?

Any physical space on a hard drive that does not belong to a partition will be displayed as “Unallocated” in Disk Management. This means that space does not exist to the operating system and you cannot write data onto it. Moreover, you will not be able to see it in Windows File Explorer, which is always one of the most important causes of hard drive not showing full capacity.

Need to delete unallocated partition on hard drive

As described above, the unallocated space cannot be used as other normal partitions to store data. And space isn’t automatically allocated to other existing partitions on the disk. In order to recover the extra space and make the fullest use of the hard drive, it is necessary to delete unallocated space on the hard drive.

How to delete unallocated space in Windows 10/8/7?

To delete unallocated partition on hard drive, you can either create a new partition on this space or merge it into an existing partition. To accomplish those jobs, you can use Disk Management or professional disk manager software.

Option 1. Remove unallocate space via Disk Management

First of all, you need to open Disk Management: Right-click “My Computer/This PC”, click “Manage>Storage>Disk Management”. Or use “Windows+R” to open Run, type “diskmgmt.msc” in the empty box and tap “OK”.

>>To create a new partition on this unallocated space

Right-click the unallocated space, and select “New Simple Volume”, then New Simple Volume Wizard will pop out, follow it to create a new partition.

Create New Volume

>>To extend an existing partition with unallocated space

Right-click the left volume that is next to the unallocated space, select “Extend Volume”. Then Extend Volume Wizard will appear, just follow its prompts, you can merge the unallocated space to the existing partition successfully.

Extend Volume

In those two methods, the unallocated space will disappear and you will get a new partition or enlarge another partition.

However, Disk Management cannot delete unallocated space in the following situations.
1. When you try to repartition removable storage devices or create a new partition on 3TB MBR Hard Drive, the New Simple Volume will be greyed out, because Windows won’t let you repartition removable storage devices, MBR disk only supports 2 TB hard disk at most, and you can only create up to 4 primary partitions on MBR disk.
2. When the unallocated space is not right behind the volume you want to extend, Extend Volume greyed out as well in Disk Management.

Option 2. Delete unallocated partition via free partition software

When you cannot create a new partition or extend another partition with the unallocated space in Disk Management, you can turn to the free partition manager: AOMEI Partition Assistant Standard. This freeware allows you to convert MBR to GPT without data loss, then you can create more partitions on a GPT disk, meanwhile, you can use it to repartition removable storage devices. Moreover, it can merge unallocated space to an existing partition easily even when they are not adjacent. Now you can download the freeware and try to remove the unallocated partition on Windows 10/8/7.

>>To create new partition on unallocated space:

Step 1. Install and launch AOMEI Partition Assistant. Right-click the unallocated space and select “Create Partition”.

Create New Partition With Unallocated Space

Step 2. In this window, you can specify the size and location of the being created partition.

Specify Partition Size

Step 3. Back to the main interface, click “Apply” to commit the pending operation.

Click Apply

>>To merge unallocated space to another partition:

Step 1. In the main interface of AOMEI Partition Assistant. Right-click the unallocated partition and go for “Merge Partition”.

Select One Unallocated Space

Step 2. In the window, the unallocated space is automatically chosen, you just need totick another existing partition and click “OK”.

Tick Another Unallocated Partition

Step 3. Click “Apply” to start merging the unallocated space to the target partition.

Apply

If there is more than one unallocated space, the "Merge Partitions" can also help merge two or more parts of unallocated space into a partition. All in all, you can successfully delete unallocated space by creating a new partition or merging it to an existing partition via this software. Besides, you can also use it to delete hidden partition.

Sum up

Apart from deleting partitions, AOMEI Partition Assistant can also help copy/move and wipe partition. For more advanced features such as partition alignment, allocating free space from one partition to another, converting boot disk between MBR and GPT styles and more, you can upgrade to AOMEI Partition Assistant Professional. To delete unallocated space in Windows Server 2012/2016/2019, etc, please try AOMEI Partition Assistant Server instead.