How to Increase C Drive Space from D Drive in Windows 11/10

Key Takeaways:

• When the C drive (system partition) is out of space or the C drive is full, the performance of the computer will be affected. To better manage your computer or upgrade your hard disk, you need to increase C drive space from D drive.
• Moving space from the D drive to the C drive can quickly expand the C drive space. In this article, we will explain in detail how to directly allocate space from D drive to C drive.
• With Disk Management, you need to delete D drive and extend C drive, but with AOMEI Partition Assistant, you can directly allocate space from D drive.

Can C drive space be increased from D Drive?

Of course, you can increase C drive space. How can I make more space on my C drive? The Windows C drive runs out of space gradually. While, the other partitions, like D drive, still have much free space. So, some people may wondering how to get space from D drive, here is a typical case from Microsoft Community:

“I have a desktop that comes with a small C drive and a large (and mostly empty) D drive. I always receive the low disk space warning on C drive. Is there any way that I can increase C drive space from D drive, other than a fresh OS installation.”

C partition is easier to get full than the other partitions because many programs are installed on system partition, a large amount of data are stored on system drive, OS running generated a lot of extra files, etc. Continue reading, this guide will provide the most effective solution to extend C drive - delete D drive and extend C drive

How to increase C drive space from D drive in Windows 11/10/8/7

Generally, to extend C drive by moving free space from C drive, you can make use of the Windows native there are two ways, using Disk Management (DM) or a third-party partition manager– AOMEI Partition Assistant. For newbies, it is recommended that you choose a third-party tool - AOMEI Partition Assistant. The tool has a simple interface and a high success rate without any experience or technical knowledge.

Below are details about those two ways.

▶ 1. Allocate Free Space from D to C Drive with partition magic

AOMEI Partition Assistant Professional is a third party partition manager which can do not only what DM can do (such as extend partition, shrink partition, delete partition, create partition and format partition), but also what DM cannot do (like move partition, wipe disk, rebuild MBR, split partition, merge partitions, etc.). To increase C drive space from D drive, you can apply its “Allocate Free Space” features, which allow you to directly allocate free space from one drive to another without causing data loss. Only 3 steps can be done:

Tip: You can download the Demo Version for a free trial.

Step 1. Right click partition D and select Allocate Free Space.

Step 2. Set how much space you want to allocate form partition D and choose C partition as a target partition.

Step 3. Preview the result after allocation. If that’s what you want, just click "Apply" on upper left to carry out the operation.

Notes:
1. If it looks not like what you want, or you want C drive to be larger, you can click Discard behind Apply and do the operations above once more.
2. You can also complete the “increase c drive space from d drive” task using Extend Partition feature of this software.

▶ 1. Increase C drive from D drive via Disk Management

Before proceeding, you should note that Disk Management can only extend C drive when there is an unallocated space very behind it. Meawhile, when you shrink a parition, you can only get the unallocated space on its the right adjacent side. That’s why you will find the Extend Volume grayed out when you shrink D drive and try to extend C drive with the unallocated space.

Therefore, to increase C drive space from D drive, you have to delete the whole D partition and make it a contiguous unallocated space for C drive.

Note: Backup important data on D partition or just transfer them to other drives.

Step 1. In Disk Management, right click on partition D and select "Delete Volume" to create unallocated space for increasing partition C.

Step 2. Right click system partition and choose "Extend Volume” to extend system partition. Still, follow the steps to complete the progress.

What if there is too much data on D drive and you do not want to delete it? The next method can satisfy all your needs. The best solutions is to use AOMEI Partition Assistant and allocate space from D drive.

Summary

This is all on how to increase C drive space from D drive in Windows 11, 10, 8, 7. With two methods provided, you can make a proper choice based on your situation. Apart from extending C drive more flexibly and securely, AOMEI Partition Assistant Professional is also able to transfer C drive to SSD, align SSD partitions, clone system disk to SSD/HDD and more. If you are running Windows Server operating system, you can try AOMEI Partition Assistant Server.