Resize/extend system reserved partition in Windows 10

Updated on: November 16, 2019

This article introduces how to resize system reserved partition on Windows 10 (32 & 64 bit). Shrink C drive to extend system reserved volume without losing data.

Can't extend system reserved partition in Windows 10 DM

Windows has some built-in utilities that helps do some basic operations. If you want to resize hard drive in Windows 10, there is Disk Management. Shrink Volume function helps decrease a partition to make Unallocated space. Extend Volume helps increase partition size by merging adjacent Unallocated space.

However, if you want to extend system reserved volume in Windows 10, this native tool cannot help you.

Because extending a partition, there must be Unallocated space in the same disk, no matter you delete or shrink another partition. The drive next to system reserved partition is volume C, which is where Operating System running from, of course you can't delete it.

If you shrink C drive with Disk Management, Unallocated space will be produced on its right side. Unallocated space cannot be combined to any non adjacent drives with Extend Volume function, except there is a tool that can move Unallocated space to the left side.

As you see, Extend Volume is disabled for the system reserved partition after shrinking C drive.

To extend system reserved partition in Windows 10, you need to run professional disk partition software.

Extend Volume disabled

Resize system reserved volume with partition editor

Unlike Windows Disk Management that can only shrink a volume towards left, partitioning software such as NIUBI Partition Editor can shrink a drive and make Unallocated space on either side. Unallocated space can be easily combined to any adjacent volume. It also can be moved if you want to extend any non adjacent partition.

Download NIUBI Partition Editor and you'll see the initial partition size and other parameters, system reserved partition is 550MB.

Main window

Steps to extend system reserved partition on Windows 10:

Step 1: Right click C: drive and select "Resize/Move Volume", drag left border towards right in the pop-up window (or enter an amount in "Unallocated space before").

Shrink C

C drive will be shrank and some Unallocated space will be generated on its left side.

C drive shrank

If you drag right border leftwards, Unallocated space will be produced on the right side.

Step 2: Right click the system reserved partition and select "Resize/Move Volume" again, drag right border towards right to combine Unallocated space.

Extend system reserved

System reserved partition is extended to 2.5GB.

Reserved partition extended

If you want to get unused space from other data volumes such as D, right click it and follow Step 1 above to shrink it. Then right click drive C and select "Resize/Move Volume", drag middle position towards right to move Unallocated space to the other side. Finally follow Step 2 above to extend system reserved partition.

No partitioning software can extend Reserved or EFI System partition in Windows 10 if you use GPT disk.

Take care of system and data

There is potential system damage risk while resize system reserved partition and C drive, so you'd better back up and use reliable software.

Better than other tools, NIUBI Partition Editor provides unique 1 Second Rollback technology, which is able to automatically reverts computer to original status in a flash if encounter any error. It also provides Virtual Mode, Cancel-at-well and advanced file-moving algorithm to help resize partitions more safely and much faster.

Besides repartitioning hard drive, it also helps you copy, convert, defrag, wipe, scan, hide partition, etc.