Expanding the System Partition in Windows 10

If the Windows 10 system partition is running out of space, expand it. There are several ways to do this.

EaseUS Partition Master: Expanding the System Partition in Windows 10

Note: In Windows 10, the options for expanding the system partition are quite limited. In many cases, you’ll need a program like EaseUS Partition Master Free to do this. With the free edition, you can manage hard drives up to 8 TB and easily expand the system partition. In the video, we’ll show you how the tool works in more detail.

Launch EaseUS Partition Master Free. You’ll now see an overview of all available partitions. To free up storage space, you must first shrink a partition.
Select the desired partition and right-click on it. In the context menu, select “Resize/Move.”
In the following menu, you can change the partition’s size using the slider or by entering the desired values.
Close the window by clicking ‘OK’ and click the “arrow” in the upper-left corner to apply the changes. This process may take a few seconds.
Once you close the window by clicking “OK,” the new free space will become visible. To enlarge the system partition, you must restart the computer.
After restarting, select the system partition (usually drive C:) and click the “Move or resize the partition” option again.
Here, you can use the slider to add the new free space.
Tip: You really only need the Pro version (for around 55 euros) if, for example, you need support for unlimited hard drive capacity or need to manage dynamic volumes.

Step 1: Preparations for expanding the system partition using Windows’ built-in tools

Alternatively, you can try using Windows’ built-in tools. Note: Free space cannot be moved in Windows. The freed-up space must be located directly behind the partition. These instructions were tested with Windows 10 Pro 22H2.

Press the “Windows” and ‘X’ keys simultaneously to open the context menu in the lower-left corner.
Select “Disk Management” and wait a moment for it to load.
Alternatively, click the “Windows icon” in the lower-left corner and type “Computer Management.” Open the app. On the left-hand side, you’ll find the “Disk Management” option.
Look for the desired partition at the bottom. The system partition is usually labeled “Windows” and is assigned the drive letter “C:”.
To extend the C system partition, you must first shrink another partition. In our example, we’ll use the second partition, “D:” (see image).

Step 2: Shrink the second partition in Windows 10

Note: In this guide, we’ll continue to use the letters C for the system partition and D for the second partition to be shrunk as examples. Different letters may be used on your computer.

Right-click on partition D, which you want to shrink, and select the “Shrink Volume” option.
Windows automatically displays the maximum amount of space that can be freed up. Select how much space you want to free up here, and make sure that the partition still has enough space remaining.
Click the “Shrink” button to start the process. Depending on the size of the partition, this process may take a few minutes.

Step 3: Extend the system partition in Windows 10

After shrinking the partition, the freed-up space should appear as “Unallocated.”

The system partition can now be extended by this amount of space.
Right-click the system partition C and select the “Extend Volume” option.
The maximum value is usually already set here. Click the “Extend” button to complete the process. This may take a little longer than the shrink operation.

Alternative: Extend the Windows 10 system partition using PowerShell

With PowerShell, Microsoft has created a powerful and comprehensive tool. Not only can it be used to repair a faulty Windows installation, but it’s also suitable for changing the size of the system partition.

First, launch “PowerShell” by clicking the “Windows icon” (four tiles) and typing the word “Power.”
The app will then be suggested. Right-click to open this suggestion. In the context menu that appears, select “Run as administrator.”
Alternatively, open “PowerShell” directly, without using the context menu. As a regular user, you can enter commands at the path C:\Users\Your Name.
To run PowerShell as an administrator, enter the command Start-Process powershell -Verb runAs. The command line will now change to C:\Windows\System32. You do not need to worry about uppercase and lowercase letters.
You are now logged in as an administrator and can get started. Next, enter the two commands diskpart and list volume. Please press the Enter key after each command.
After a few moments, the available partitions will be displayed. These are sorted by volume followed by a number.
To extend the system partition C:, enter the command select volume #. # stands for the number. In our example, the command would be select volume 2.
The partition is now selected. To enlarge it, simply enter the command extend size=#. The value for # must always be entered in megabytes (MB). For example, extend size=2048.

How to Enlarge the System Partition in Windows 11 – A Concise Step-by-Step Guide

An overcrowded system partition slows down updates and programs; follow these steps to free up space—safely, clearly, and without technical jargon.

Back up your data first – Open “Control Panel > Backup and Restore (Windows 7)” and create a full system image on an external USB hard drive; additionally, back up your personal folders using OneDrive or “File History” so that nothing is lost in the worst-case scenario.
Secure Windows – Disable BitLocker for drive C by clicking “Suspend protection” in “Control Panel > BitLocker Drive Encryption,” and then set a restore point in “System Properties > System Protection” so you can immediately undo any changes if necessary.
Free up space – Launch “Disk Management” using Win + X and select “Disk Management,” or in Windows 11, go to “Settings > System > Storage > Disks & Volumes,“ select your data partition (usually D), and choose ”Shrink Volume,” adjusting the maximum size displayed to free up exactly the amount of space you want to allocate to C.
Position the gap correctly – The newly created unallocated space must be directly to the right of C; if an OEM or recovery partition is in between, move it to the end of the SSD using “EaseUS Partition Master Free,” “MiniTool Partition Wizard Free,” or “AOMEI Partition Assistant Standard” until the gap seamlessly adjoins C.
Extend the system partition – Now right-click on C in the same view and select “Extend Volume”; the wizard will add the adjacent free space and extend your system drive in a matter of seconds.
PowerShell method for exact values – Open PowerShell as an administrator, type “diskpart,” then “list volume,” “select volume ,” and “extend size=” to add exactly 4096 MB, for example, if you don’t want to use the entire gap or if the graphical interface isn’t working properly.
When Third-Party Tools Are Useful – If “Extend Volume” is grayed out, the free space isn’t contiguous, BitLocker is still active, or you’re using a dynamic disk, the tools mentioned above will reliably get the job done; download them exclusively from the manufacturer’s website and do not select any additional programs during installation to avoid adware.
Common Pitfalls at a Glance – Grayed-out menus are almost always caused by non-adjacent free space or active BitLocker; if your hard drive still uses the old MBR layout and is larger than 2 TiB, convert it to GPT beforehand using “mbr2gpt /convert”; if the Windows Recovery Environment no longer works after moving a recovery partition, re-enable it with “reagentc /enable”.