How to Add More Space to C Drive in Windows 11

by John, Published on: July 12, 2021

System C: drive is getting full after running Windows 11 computer for a period of time. It is most common issue to Windows computer users. Many types and large amount of files are saving in C drive continuously, of course it becomes full sooner or later. Nobody likes to recreate partitions and reinstall operating system and all programs. Many people ask whether it's possible to add more space to C drive in Windows 11 laptop, desktop or tablet without losing data. The answer is yes. In this article, I'll introduce full solution to add space to system C drive in Windows 11 computer.

1. How to add adjacent Unallocated space to C drive

Unallocated space is kind of disk space that is not allocated to any partition. Besides creating new volume, Unallocated space can be added to other partition in Windows 11 computer. Another kind of disk space is free space in an allocated partition. You can add free space to C drive in Windows 11 computer, but firstly you must delete or shrink partition and convert free space to Unallocated.

Windows 11 native Disk Management tool has the ability to change partition size, but it can only extend a NTFS partition by deleting the contiguous partition on the right. In other words, if you want to extend C drive in Windows 11 without any software, you must delete D drive to get contiguous Unallocated space on the right. In addition, D must be a Primary partition. Otherwise, you still cannot extend C drive with Disk Management tool.

Steps to add Unallocated space to C drive in Windows 11 with Disk Management:

  1. Press Windows + X keys and click Disk Management in the list.
  2. Right click the adjacent partition D (or E) and select "Delete Volume", then all disk space of this volume will be changed to Unallocated.
  3. Right click C: drive and select "Extend Volume". Follow up the pop-up wizard to add the adjacent Unallocated space to C drive.

Caution: do not delete partition if you installed programs in it or if there are special files. Remember to move files before deleting partition.

2. How to add nonadjacent Unallocated space to C drive

Few people will try to increase C drive space by deleting other partition. Most of people will shrink the adjacent partition D to get Unallocated space. If you've did this in Windows 11 Disk Management, you cannot extend C drive. Extend Volume option is grayed out because this Unallocated space is nonadjacent to C drive. To add this nonadjacent Unallocated space to C drive, you must move it to the left in advance.

Steps to add nonadjacent Unallocated space to C drive in Windows 11:

  1. Download NIUBI Partition Editor, right click D: drive and select "Resize/Move Volume" option. Drag the middle block towards right in the pop-up window. Then Unallocated space will be moved to the left.
  2. Right click C: drive and select "Resize/Move Volume" option again, drag right border towards right to merge this Unallocated space.
  3. Click Apply on top left to take effect.

Watch the video how to operate.

Windows 11

3. How to add free space to C drive from D or E

If you have not shrunk any partition to get Unallocated space, shrink with NIUBI Partition Editor. Better than Disk Management, NIUBI can make Unallocated space on the left when shrinking a partition, so C drive can be extended easily without moving Unallocated space.

Steps to add free space to C drive from D/E in Windows 11:

  1. Right click the adjacent D: drive and select "Resize/Move Volume" option, drag left border towards right in the pop-up window, or enter an amount in "Unallocated space before".
  2. Right click C: drive and run "Resize/Move Volume" again, drag right border towards right in the pop-up window, then the adjacent Unallocated space will be added into C drive.
  3. Click Apply on top left to take effect.

If you want to add space to C drive from nonadjacent partition (here is E:), there's an additional step to move Unallocated space to the left before adding to C drive. Watch the video how to add space to C drive in Windows 11 from other partitions:

Windows 11

4. How to add space to C drive with another disk

In some Windows 11 computers, there's no available space on the same disk. For example, there's only C drive on the system disk, there are other partitions on the same disk but there's not enough free space. In that case, no software can help you add space to C drive from another different/separate disk. But you can increase C drive space with another disk by cloning.

Steps to add space to C drive with a larger disk in Windows 11:

  1. Insert a larger disk to this computer.
  2. Follow the steps in the video to clone system disk to this larger one. Remember to click the option to turn off computer after clicking Apply.
  3. Replace system disk with this larger one, or change BIOS to boot from the larger disk.

Besides adding space to C drive in Windows 11/10/8/7/Vista/XP computer, NIUBI Partition Editor helps you do many other disk partition management operations.

Download