EaseUS Partition Master

A simple partition tool to manage disk space in Windows 10

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

Updated by Daisy on Feb 25, 2021
Written by Brithny

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 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 10. Any suggestions will be appreciated!

Merge unallocated space to system partition in Windows 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 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 10 to extend system partition if the unallocated space is right behind it. Otherwise, you might need a third-party Windows 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. 

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 10:

Step 1. Locate the Target Partition

To start extending partition, you should first 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 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 Operation" button and click "Apply" to keep all the changes. 

Video Tutorial - How to Move Unallocated Space to C Drive on Windows 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.

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 has appeared, 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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Updated by Daisy

Daisy is the Senior editor of the writing team for EaseUS. She has been working in EaseUS for over ten years, starting from a technical writer to a team leader of the content group. As a professional author for over 10 years, she writes a lot to help people overcome their tech troubles.

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Written by Brithny

Brithny is a technology enthusiast, aiming to make readers' tech life easy and enjoyable. She loves exploring new technologies and writing technical how-to tips. On her spare time, she loves sharing things about her favorite singer - Taylor Swift on her 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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How to Partititon a Hard Drive on Windows 10/8/7

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