How to resize system partition on Windows 10

Updated on: November 16, 2019

This article introduces how to resize system partition on Windows 10 (32 & 64 bit). Resize system volume and data partitions without losing data.

Nowadays, many Windows 10 computers including DIY desktop and OEM laptop have two hard disk drives. One SSD for operating system and programs, the other one for files storage. But because SSD is still expensive, its size is not big enough. No matter which type of disk you use, you are very likely encounter the disk space issue, for example:

Luckily, you can resize system partition on Windows 10 without starting over. To do this, there are two options with Windows native Disk Management and 3rd party professional partition editor software. Disk Management is easy and safe, but in some situations you can't resize system volume for Windows 10 computers.

Resize system partition with Windows 10 Disk Management

Firstly, let's see how to change size of system volume with Windows built-in utility. To start Disk Management, there are two options:

To shrink system partition:

  1. Right click it and select Shrink Volume.
  2. Click Shrink to use default maximum space or enter an amount manually first.

Shrink C drive

When extending the system drive, there must be contiguous Unallocated space on the right side of it.

To extend system partition:

  1. Right click it and select Extend Volume.
  2. Simply click Next till Finish in the pop-up Extend Volume Wizard window.

Extend volume

Limitations to resize system volume with Disk Management

When shrinking volume:

  • Only NTFS partition is supported.
  • You can only shrink little space if there are unmovable files are located in this partition.
  • If there is file system error or due to some special reason, you can't shrink a volume even if there is free space in it.
  • You can only make Unallocated space on the right side of this volume.

When extending volume:

  • Only NTFS partition can be extended.
  • Extend Volume can only expand the partition with contiguous Unallocated space on its right side.
  • You cannot extend system partition by shrinking any other volumes.
  • Disk Management can't move partition, so you cannot extend a partition with any non adjacent Unallocated space.

In a word, Disk Management can only shrink NTFS partition towards left and make Unallocated space on the right side. It can only extend a volume by deleting the adjacent one.

Better way to resize system drive with partition editor

Professional partition manager software is more powerful and there are many choices in the market. However, you'd better select the safe one, the unreliable software could cause system damage and data loss. Because all parameters of disk, partitions and files must be modified, files in some partition must be moved to new locations, system files must be updated. Any slight error leads to boot fail and/or partition corrupt.

Better than other tools, NIUBI Partition Editor provides unique 1 Second Rollback, Cancel-at-will and Virtual Mode technologies to ensure system and data intact. Hot-Resize technology and advanced file-moving algorithm to help resize partition much faster.

Download it and you'll see initial disk partition size and configuration on the right. Available operations are listed on the left.

Main window

To shrink system partition C on Windows 10 with NIUBI:

Right click it and select "Resize/Move Volume" feature, drag right border towards left in the pop-up window:

Resize partition C

System partition is shrunk towards left and Unallocated space is made on the right side.

Shrink C

If you drag left border towards right in the pop-up window, Unallocated space will be produced on the left side of C drive.

To extend system partition on Windows 10:

In most cases, data volumes are on the right side of system partition, so shrink the contiguous partition (D:) towards right and make Unallocated space on the left side. To do this:

Right click drive D and select "Resize/Move Volume", drag left border towards right in the pop-up window.

Shrink D

Then right click system partition C and select "Resize/Move Volume" again, drag right border towards right to combine the Unallocated space.

Extend C drive

If there is not plenty of free space in the contiguous partition (D:), you can shrink the non adjacent partition (E:) to make Unallocated space on the left. Before extending system C drive, you need an additional step to move Unallocated space from right side of D to the left.

To do this: right click drive D and select "Resize/Move Volume", drag middle position towards right in the pop-up window.

Move drive D

To resize system partition on Windows 10 (32 and 64 bit), you just need to drag and drop on the disk map, shrink any data volume to get Unallocated space, and then combine into system C drive.

Besides resizing and moving partitions, NIUBI Partition Editor helps you do many other disk and partition management operations.