How to Add More Space to C: Drive in Windows PC/Server

By Jordan, Updated on: May 24, 2022

This article introduces how to add space to C drive without losing data. 3 ways to add more space to C drive from D/E or with other disk. Select the corresponding method according to your own disk partition configuration.

Applies to: Windows 11, Windows 10, Windows 8, Windows 7, Windows Vista, Windows XP, Windows Server 2022, Windows Server 2019, Windows Server 2016, Windows Server 2012 (R2), Small Business Server 2011, Windows Server 2008 (R2) and Windows Server 2003 (R2).

1. Benefit to add more space to C: drive in Windows server and PC

Most of Windows computer users encountered the problem that system C: drive is running out of space and the annoying Low Disk Space alert pops up frequently. When it happens, the fastest way to solve this problem is by extending C drive. That means add more space to C drive from other partitions. It costs such a long time if you back up everything, recreate partitions and restore from backup.

To add more space to C drive in Windows 10/11 and Server 2008 to 2022, there are 2 kinds of tools - Windows native Disk Management and third party partitioning software. Disk Management can only help you delete the contiguous partition D (or E) and add its space to C drive. In addition, the adjacent partition D must be Primary. If you want to add free space to C drive by shrinking other volume, Disk Management cannot help you, learn why.

There are many partition software to help move free space, but you'd better back up in advance and run the safest tool, because there is potential data loss and system damage risk. While re-partitioning disk drive, the parameters of associated disk, partition and files must be modified correctly. Any software error or hardware issue could cause part of the parameters failed to be modified. If it happens, system, partition and/or data will be damaged.

Better than other tools, NIUBI Partition Editor has unique 1 Second Rollback, Cancel-at-well and Virtual Mode technologies to protect system and data. Furthermore, it is much faster because of the advanced file-moving algorithm.

2. How to add space to C drive from D drive (adjacent)

In most of PCs and servers, there's another partition such as D or E on the same disk. And in most cases, there's plenty of free space in either partition. You can shrink this partition, then part of free space will be converted to "Unallocated", and then you can add this Unallocated space to C drive. During this process, Operating System, programs and anything else keep the same with before.

To add space to C drive in Windows 11/10/8/7/Vista/XP, NIUBI Partition Editor has free edition to help you. The steps to add free space to C drive in Windows Server 2008/2012/2016/2019/2022 are the same, but you need the server or higher edition.

Steps to add space to C drive from D drive(adjacent partition):

  1. Download NIUBI Partition Editor, right click D: drive and select "Resize/Move Volume", drag left border towards right in the pop-up window. (Or enter an amount in the box of "Unallocated space before"). Then Unallocated space will be made on the left side of D.
  2. Right click C: drive and select Resize/Move Volume again, drag the right border towards the right side in the pop-up window, then Unallocated space will be added into C drive.
  3. Click Apply on top left to execute. (Any operations before this step only work in virtual mode.)

Watch the video guide how to operate.

Video guide

If the contiguous partition is E in your computer, simply replace D with E in the steps above.

3. How to add space to C drive from E (nonadjacent partition)

In some computers, there is not enough free space in the contiguous volume D. In that case, you can shrink any nonadjacent partition on the same disk. Before adding Unallocated space to C drive, there's an additional step to move partition D to the right.

Steps to add free space to C drive from E (non-adjacent partition):

  1. Shrink E: drive and make Unallocated space on the left with "Resize/Move Volume" feature.
  2. Right click D: drive and select "Resize/Move Volume", drag the middle  of D drive towards right in the pop-up window, then Unallocated space will be moved to the left.
  3. Right click C: drive and add Unallocated space into it with "Resize/Move Volume".
  4. Click Apply to take effect.

Video guide

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

In few computers, there's no data volume on the same disk, or the data volume(s) are full. Some people are wondering if it is possible to add space to C drive from another disk. No matter you use physical disk or VMware/Hyper-V virtual disk, no software can add space to C drive from a different/separate disk.

In this case, you have 3 options according to the configuration of your own disk:

  1. If you use physical SSD/HDD and there's other data volume but it's full, you may move this data partition to another disk, delete it and add its space to C drive.
  2. Clone whole disk to a larger one and extend C drive with additional disk space.
  3. If you use virtual disk, follow the steps to expand disk in VMware or Hyper-V. After that, additional disk space is shown as Unallocated at the end of original disk, then follow the steps above to combine into C drive.

Besides adding space to C drive without losing data, NIUBI Partition Editor helps you do many other operations such as merge, convert, defrag, wipe partition, scan bad sectors, optimze file system and much more.

DOWNLOAD