EaseUS Partition Master

A simple partition tool to manage disk space in Windows 10

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How to Add Space to C Drive to Increase C Drive Space

Updated by Tracy King on Aug 27, 2021
Written by Daisy

Why Do You Need to Add Space to C drive

Case 1. "I have an 18GB disk drive that has been split into partitions: C: and D:. C: has about 4GB and D: has about 14GB. However, my C: drive is running out of space. How can I add space to C drive from D?"

Case 2. "I am running windows 2000 server, the C: Drive is only a 4 GB partition and 60GB on its D: Drive. How can I increase C drive space so I can do Windows updates and install a program?"

Case 3. "Well when I reformatted my computer I ended up making 2 partitions. I realized how useless the second one was so I deleted it. How can I now add space to C drive?"

There are many similar cases. Low disk space is one of the issues that many users may encounter. After long time usage of your computer, it pops up a warning message says "Low Disk Space – You are running out of disk space on the system (C:) To free space on this drive by deleting old or unnecessary files, click here..." 

c drive is out of space

Your system partition doesn't have enough free space. And you need to increase your C drive space. If you are in a hurry, here's quick access to adding space to C drive to increase C drive size: 

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Is It Possible to Increase C Drive Space

Yes, it is. You can increase C drive space. There are basically two major directions. One is to extend C drive Windows 11/10, and the other is to free up C drive space Windows 11/10. The ideal solution is adding space to C drive to increase C drive space because cleaning up space may cause data loss. You can add more space to existing primary partitions and logical drives by extending them into adjacent unallocated or free space on the same disk. Usually, there are three ways to add space to the C drive in Windows 11, 10, 8, and 7. You can use EaseUS Partition Master, try Windows Disk Management or use a command line.

Three Ways to Add Space to C Drive to Increase C Drive Space 

To completely solve the low disk space problem, we should allocate free space to C drive from unallocated space or other partitions. Here are three ways to add more space to the C drive.

Solution 1. Add Space to C Drive with EaseUS Partition Master

For average users who know little about Disk Management, how to add space to C drive is not an easy task. It is true that Windows built-in Disk Management tool can add space to C drive. But the precondition is that there must be continuous space behind C drive. Otherwise, you cannot increase C drive space with it, like Windows Vista, Windows 2008,   or Windows 7 Disk Management cannot move the partition to let continuous space behind the C drive which you want to extend. The good news is there is a simpler way. You can use third-party software to add space to C drive.

EaseUS partition software is the perfect specialist partition manager to help you move space to your C drive in Windows 11, 10, 8, and 7.

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Watch this video to see how to adjust your C drive easily and quickly with EaseUS Partition Master.

Here is a step-by-step guide on how to use it:

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. 

Bouns Tip: Extend Low Space C Drive with EaseUS Partition Master

When your C drive is running out of space, you can apply the new feature of EaseUS Partition Master to adjust low disk space in 1-click.  Here's the detailed guide:

Step 1. Click "Adjust with 1-Click" to extend C drive.

When your C drive is out of space, you will see the Low Disk Space alert on EaseUS Partition Master. Click the Adjust button to extend it.

How to Adjust Low C Drive Space Step 1

Step 2. Click "OK" to extend C drive automatically.

By clicking "OK", EaseUS Partition Master will automatically allocate space to your C drive to solve the low space issue.

How to Adjust Low C Drive Space Step 2

Extra Option: You can also click "Manual Adjustment" to extend the C drive manually.

When turning to Manual Adjustment, select the C drive, and drag dots rightward to add more space to C drive. Click "OK" to confirm.

Manually Adjust Low C Drive Space

Step 3. Confirm to resolve low disk space in C drive

Click the "Execute Operation" button at the top corner and start all pending operations by clicking "Apply".

How to Adjust Low C Drive Space Step 3

Solution 2. Add Space to C Drive with Disk Management in Windows 11/10

You can also increase space in C drive using Disk Management. Only if there is unallocated space very behind C drive, can it be increased Disk Management? Otherwise, the C drive's extend volume option will be greyed out. 

Step 1. Right-click "This PC" and go to "Manage > Storage > Disk Management".

Step 2. Select the disk you want to extend, right-click it and click "Extend Volume".

extend c drive spcae with disk management

If you don't have unallocated space, choose the partition that is next to C drive and select "Shrink Volume" to create some free disk space. Then, select the disk you want to extend, right-click and choose Extend Volume to increase disk space.

Solution 3. Add Space to C Drive with a Command Line

If you are familiar with command lines, you can add space to C drive with a command line. Follow the steps below:

Step 1. Open a Command Prompt and type diskpart.

Step 2. At the Diskpart prompt, type the following commands:

  • list volume
  • select volume
  • extend size
  1. List volume: Displays a list of basic and dynamic volumes on all disks.
  2. Select volume: This selects the basic volume number that you want to extend into contiguous, empty space on the same disk.
  3. Extend: This extends the selected volume by size in megabytes (MB).

To Sum Up

Disk Management can help us extend system C drive in seconds. However, the disadvantage is that you have to format other drives to allocate free space from one partition to another. The command line also has the same limitation. So, the best way to add space to C drive is by using EaseUS Partition Master. This software makes it effortless to partition hard drives and take full advantage of your disk space. Besides the partition manager, EaseUS Partition Master provides partition recovery and disk or partition copy features.

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Updated by Tracy King

Tracy joined in EaseUS in 2013 and has been working with EaseUS content team for over 7 years. Being enthusiastic in computing and technology, she writes tech how-to articles and share technical solutions about Windows & Mac data recovery, file/system backup and recovery, partition management and iOS/Android data recovery.

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Written 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.

Read full bio

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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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