How to Merge Unallocated Space Windows 10/7

Jean updated on Sep 10, 2020 to Partition Master | How-to Articles

You can merge unallocated space Windows 10 or Windows 7 with the traditional Windows Disk Management or the optimizing third-party partition magic software - EaseUS Partition Master, which allows the most direct way to add unallocated space to C drive or other disk volumes without affecting data.

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 Windows 10 is supported

What Is Unallocated Space

The unallocated space is explained as a block of free space that Windows hasn't assigned a drive letter to it. Without allocation, the operating system won't recognize the space nor allow for writing files to it. To make full of the unallocated space on your hard drive, you can either create a new partition on it or merge it into an existing partition.

In Windows, the Disk Management program is where you can view the unallocated space, and this is how it looks like:

unallocated space in windows disk management

In addition, third-party alternatives also come with a disk map where unallocated space will show up. On EaseUS Partition Master, this is how unallocated space displays itself:

unallocated space in easeus partition master

How Do I Merge Unallocated Disk Space in Windows 10

Since the unallocated space is treated as a missing part of used space on a hard drive in Windows, why not put it in practical use right now? If you're interested in merging unallocated disk space instead of creating a new one, there are two ways for you to safely transfer the unallocated space.

  1. 1. Add unallocated space to C drive
  2. 2. Merge unallocated space to a data partition

Both Windows Disk Management and EaseUS Partition Master enable the possibility of merging the unallocated space to the desired partition, but they differentiate each other regarding whether the two are continuous or not.

Can I Combine Two Unallocated Space

Are you seeing two more unallocated space on your computer hard drive like me? Never mind. You can manage as many unallocated partitions as you can with an appropriate partition tool. Though both tools are technically capable to handle the unallocated space, they function in totally different ways. The more unallocated space you get, the more complicated for you to solve in Disk Management. Whereas EaseUS Partition Master comes handy for the purpose of making it fast, meanwhile getting it done without affecting other partitions and present data!

two unallocated space

How to Add Unallocated Space to C drive

To merge unallocated space to the C drive with Windows Disk Management, you need to use the "Extend Volume" function. You must make sure that the unallocated space is continuous to the system partition. For example, it should be C: + Unallocated + D:, so that you can directly right-click on the C drive and choose "Extend Volume..." to start merging the unallocated space to the C drive. Open the Disk Management and try the steps one by one.

Step 1: Install and run Disk Management. Right-click the partition you want to add the unallocated space to and then choose Extend Volume to merge Partitions (e.g. C partition). 

Step 2: Follow the Extend Volume Wizard and then click Finish. 

Step 3: In the pop-up window, you will realize the size of partition has been increased.

merge unallocated space to c drive under disk management

In any case, the unallocated space is not on the neighboring right side of the C drive, you cannot add unallocated space to the C drive because the Extend Volume greyed out.

By contrast, it's more flexible to have EaseUS Partition Master to deal with either an adjacent or non-adjacent unallocated space in Windows 10/8.1/8/7/XP/Vista. What are the overwhelming features that make it stand out when it comes to a comfortable and straightforward way to add space to the C drive without losing a single data?

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 Windows 10 is supported

1. Resize/Move partition

Where is the unallocated located? Has it to be on the right side of the C drive? What about the C drive and unallocated space is separated by the drive D, E or F? It doesn't matter even you catch up in all the situations because you are still empowered to use a simple 'drag and move' method to swallow all the unallocated space into the system drive.

2. Allocate Space

This feature is newly added in the recent software update. The most amazing part is that you don't even consider whether you currently have unallocated space or not, which saves an essential step to shrink one partition to create unallocated space in order to extend the C drive before. Windows Disk Management is not expected to own this feature in the coming days.

How to Merge Unallocated Space to C Drive in Windows 10/7 with EaseUS Partition Master

As you've learned in advance, EaseUS partition manager software could handle one more unallocated space that is either continuous or non-continuous with the C drive, or other disk volumes you set your mind to spare the unallocated space. What's more, it is competent enough to get you out of trouble to solve low disk space even there is no unallocated space to extend the system partition.

#1. Merge Unallocated Space in Windows 10 (non-adjacent)

Step 1. Locate the Target Partition

To start extending partition, you should first launch EaseUS Partition Master and locate the target partition which you would like to extend.

Step 2. Extend the Target Partition

1. Right-click on the target partition which you would like to extend and select "Resize/Move".

Select target partition to extend

2. Drag the partition panel rightward or leftward to add unallocated space into your current partition and click "OK" to confirm.

choose another drive to allocate space

3. If there is no or not enough unallocated space on your disk, use the advanced partition resizing function to directly allocate free space from other partitions to the target drive without deleting or formatting.

Find the "Allocate XX space from" option, then click "Select partition". Choose the partition from which you want to allocate space. Drag the partition panel rightward or leftward to resize the partition you want to extend. Then click "OK" to confirm.

choose another drive to allocate space

Step 3. Execute Operations to Extend Partition

Click the "Execute Operation" button and click "Apply" to keep all the changes. 

finish extending partition
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 Windows 10 is supported

#2. Merge Windows 10 Unallocated Space on a Disk Larger than 2TB

If your hard disk is larger than 2TB and initializes it to MBR, it will divide it into two unallocated space in Disk Management. As we know, MBR only supports disk up to 2TB. You need to convert MBR to GPT before merging unallocated space larger than 2TB. 

merge unallocated space larger than 2TB 1

You may try the Disk Management to convert but it is grayed out. Because the built-in tool can only convert partition format on an empty disk. Don’t worry. Here is a better solution to convert partition style without wipe any data - EaseUS Partition Master.

Step 1. Download and launch EaseUS Partition Master on your Windows computer.

Step 2. Right-click the MBR disk that you want to convert and choose "Convert to GPT".

convert MBR to GPT - 1

Step 3. After that, find and click the "Execute 1 Operation" button on the toolbar and choose "Apply" to start the conversion. You need to restart your device to enable this change.

convert MBR to GPT - 2

Now you can see the two unallocated space becomes one. Then you use Disk Management to merge it to another disk or apply EaseUS Partition Master to merge unallocated space in Windows 10.

merge unallocated space larger than 2TB 2

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Frequently Asked Questions

Why Choose EaseUS Partition Master?

"I've used Partition Master Professional many times to create, delete, format, move, rename, and resize partitions."PCWorld

"Partitioning tools have come a very long since the days of complicated command line utilities and EASEUS Partition Master is one of the most advanced programs available."TECH ADVISOR

"I love that the changes you make with EaseUS Partition Master Free aren't immediately applied to the disks. It makes it way easier to play out what will happen after you've made all the changes."Lifewire

Will the "Migrate OS" feature transfer the Windows system files only or the whole C drive?

To ensure that the migrated system will boot normally, the Migrate OS feature will transfer all the files in the system and the boot partitions. Generally, the boot partition is the C drive so the transfer will include all the files in C.

Does EaseUS Partition Master license apply to multiple computers?

The license of Partition Master Professional and Server editions can be used on 1 computer only, while that for for the Technician and Unlimited editions can be used on multiple machines.

What is the difference between EaseUS Partition Master Trial version and the Free version?

Free is for home users only, with most basic functions available such as partition resize and clone. While trial can help you understand how this product works and test what a full license can do on a business or server OS machine.

Will it cause any data loss after resizing the partition in EaseUS Partition Master?

Generally, it will not cause any data loss or boot issue by resizing a partition. However, in order to protect your data, we suggest that you backup the partition before resizing, in case of any unexpected situations such as power outages, computer hardware failures, etc. You can use EaseUS Todo Backup to backup the partition and its trial version is fully functioned for 30 days.

What should I prepare before resizing the partition?

On the partition that is going to be operated, there might be some files being occupied by other programs. To ensure a successful operation, we suggest that you close all the unnecessary software before resizing that partition. Otherwise, EaseUS Partition Master will detect the partition being locked by the other software and require a reboot to resize the partition under boot mode.

About EaseUS Partition Master

All-round disk & partition management software for personal and commercial use. Let it manage your storage drive: resize, format, delete, clone, convert, etc.

Video Tutorial

How to Partititon a Hard Drive on Windows 10/8/7