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[New] How to Add Unallocated Space to C Drive in Windows 10

Adding unallocated space to C drive is a good way to extend C drive, especially when it's out of space. On this page, you'll learn how to add unallocated space to C drive in Windows 11/10/8/7 with two hard drive managers - EaseUS Partition Master and Disk Management.

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Updated on Apr 19, 2024

Can I Move Unallocated Disk Space to C Drive in Windows 10

I partitioned my laptop disk into two partitions, partition C, and partition D when I bought it two years ago. The C drive is only 11/10 GB and D drive is 65 GB. Now I find that the system drive is too small to perform well. So I want to shrink D drive to create some unallocated space, and then I can extend C drive with unallocated space. However, I have no idea how to merge unallocated space into C drive. I am using Windows 11/10. Any suggestions will be appreciated!

Merge unallocated space to system partition in Windows 11/10 is an easy and efficient solution when C drive is full problem happens. Have you ever encountered such a situation? Don't worry! This page will talk about how to merge unallocated space to C drive to increase system partition space with a third-party Windows 11/10 partition magic tool. Read it and you can find a step-by-step guide about how to do the job. 

How to Add/Move Unallocated Space to C Drive in Windows 10 [Easy]

Usually, you can easily add unallocated space to C drive by Disk Management in Windows 11/10 to extend system partition if the unallocated space is right behind it. Otherwise, you might need a third-party Windows 11/10 partition tool to help you do the job. EaseUS partition software is a reliable one. It could be much easier to move unallocated disk space to C drive in all Windows OS with the help of this program. 

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Here are two functions of EaseUS Partition Master to extend C drive space: 

If your C drive doesn't have enough space to allocate, you can use Allocate Space in EaseUS Partition Master to add disk space from other drives to C drive.

It has no requirements for the location (right side/ left side/ end of the drive). 

Learn how to add and move unallocated space to C drive in Windows 11/10:

Step 1. Locate the Target Partition.

Go to Partition Manager, locate the target partition and select "Resize/Move".

Select target partition to extend

Step 2. Extend the Target Partition.

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

choose another drive to allocate space

Extra Option: Get Space from Another Drive

If there is not enough unallocated space on your disk, right-click on a big partition with enough free space, select "Allocate space".

Then select the target partition that you want to extend at the allocate space to column.

choose another drive to allocate space

Step 3. Execute Operations to Extend Partition.

Drag the dots of the target partition into the unallocated space and click "OK".

finish extending partition

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

Video Tutorial - How to Move Unallocated Space to C Drive on Windows 11/10/8/7

Before reading the tutorial, you can watch the video and start with 1:11 to learn how to add unallocated space to extend c drive.

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Apart from extending C drive with unallocated space on Windows 10, Windows 11 users can also apply this partition manager software - EaseUS Partition Master to extend c drive in Windows 11 on their own like an expert.

Also, don't for get to share this tool with your friend to help them manage disk space size wisely:


How to Add Unallocated Space to C Drive with Disk Management

In any case, the unallocated space is not on the right behind the C drive. You can not add it to the hard drive because the Extend Volume is greyed out. If your unallocated space is adjacent to C drive, you can get Disk Management to move unallocated space in Windows 10.

First, you need to open Disk Management by pressing Windows + X and enter the interface. Then, Disk Management appears. Right-click the C drive, and choose the Extend Volume to extend the C drive with the unallocated space.

disk management extend volume

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About the Author

Updated by Roxanne

Roxanne is one of the main contributors to EaseUS and has created over 200 posts that help users solve multiple issues and failures on digital devices like PCs, Mobile phones, tablets, and Macs. She loves to share ideas with people of the same interests.

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Written by Brithny

Brithny is a technology enthusiast, aiming to make readers' tech lives easy and enjoyable. She loves exploring new technologies and writing technical how-to tips. In her spare time, she loves sharing things about her game experience on Facebook or Twitter.

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  • 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. I also think the overall look and feel of EaseUS Partition Master Free makes whatever you're doing with your computer's partitions easy.

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  • Partition Master Free can Resize, Move, Merge, Migrate, and Copy disks or partitions; convert to local, change label, defragment, check and explore partition; and much more. A premium upgrade adds free tech support and the ability to resize dynamic volumes.

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  • It won't hot image your drives or align them, but since it's coupled with a partition manager, it allows you do perform many tasks at once, instead of just cloning drives. You can move partitions around, resize them, defragment, and more, along with the other tools you'd expect from a cloning tool.

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