To merge two partitions in Windows 10, back up the files on the second partition, then open Disk Management, right-click that partition, and select Delete Volume. Next, right-click the partition to its left, select Extend Volume, and add the new unallocated space. Deleting a partition erases everything on it, so copy your files off first.
Applies to: Windows 10. Checked against Microsoft Learn on September 26, 2026.
Windows has no one-click merge. You combine two partitions by removing the second one and growing the first. The two must be next to each other on the same disk.
Step 1: Back up the second partition
Copy everything you want to keep from the partition you’ll delete, such as D:, to another drive or to cloud storage. See how to back up Windows 10.
Step 2: Delete the second partition
- Right-click Start and select Disk Management.
- Right-click the partition on the right, such as D:, and select Delete Volume.
- Read the warning and select Yes. The partition becomes Unallocated space.
Step 3: Extend the first partition
- Right-click the partition on the left, such as C:, and select Extend Volume.
- Select Next, keep the maximum space, and select Next and Finish.
The two partitions are now one. For more detail and help when Extend Volume is greyed out, see how to extend the C drive in Windows 10.
Frequently asked questions
Can I merge partitions without losing data?
Not with Windows’ own tools. The second partition has to be deleted, so copy its files first and put them back afterwards.
Can I merge partitions that aren’t next to each other?
No. Disk Management can only extend into space directly after a partition. If a recovery partition sits between them, the merge won’t work.
How do I split a drive instead?
See how to partition a hard drive in Windows 10.
For the delete step on its own, see how to delete a partition in Windows 10.
Microsoft’s guide is Disk Management in Windows. More help is on our Windows Help & Guides page.
Matt Jacobs has been working as an IT consultant for small businesses since receiving his Master’s degree in 2003. While he still does some consulting work, his primary focus now is on creating technology support content for SupportYourTech.com.
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