How do I join partitions in Windows

[Top 2 Ways] Merge Partitions in Windows 10 - Free & Effective

Why merge partitions in Windows 10?

Partitions merging refers to combining two partitions into one partition, or combining a partition with unallocated space on the hard drive to expand the space of a partition.

For example, if your hard drive is not properly partitioned and drive C is becoming full, but partition D has enough free space, you can merge drives C and D to resolve this issue.

In addition, if there are some partitions on the hard drive, it is inconvenient for you to manage them. Suppose you store different data on many different partitions. If you want to open one of these, you might forget where the data is stored.

Merge partitions with Disk Management

Windows 10 Disk Management can help you merge partitions. But you cannot merge two partitions directly with the tool, so you need to delete the partition first and use "Extend Volume" function in Disk Management.

I. Open Disk Management. You can type “diskmgmt.msc” in the Run box, or right-click This pc, and choose Manage > Computer management > Data storage > Disk management.

II. Find the two partitions you want to merge, and then delete one partition. For example, if you want to merge drive C: and drive D: you need to delete drive D :. Right click on partition D: and select “Delete Volume”.

Note: Note that all data saved on drive D: will be lost. You should create a backup of drive D: first.

III. And then right click the system partition and choose “Extend Volume” option.

IV. Follow the "Add Volume Wizard" and accept the default options to merge two partitions in Windows 10.

As you can see, this feature is only available when the unallocated space is next to the partition you want to operate.

Freeware: Merge Windows 10 partitions without losing data

If you want to merge two partitions or merge a partition with an unallocated space without data loss, you can use the free partition manager - AOMEI Partition Assistant Standard. It supports combining two partitions or adding the non-contiguous unallocated space to one partition easily and effectively without losing any data.

Free download the software and read the below guide to merge two partitions in Windows 10 without data loss.

Step 1. Install and run it. Right click on the partition you want to merge (Here is partition C :) and select “Merge partitions“.

Step 2. Select the partition to be merged (e.g. * Volume) and click on "OK“.

Step 3. Click on "To run" and "Further“To merge the partitions.

Only two partitions can be merged at a time, and the two partitions must be adjacent. However, it is available to merge two or more pieces of unallocated space into one partition, regardless of whether or not the unallocated space is next to the partition being merged.
You can merge the data partition into the system boot drive, but you cannot merge a system boot drive into the data partition.
If you want to combine two partitions in Windows Server, you can try AOMEI Partition Assistant Server.


By now you have surely recognized how to merge partitions in Windows 10. If there is contiguous unallocated space behind the partition you want to extend, you can combine the partition with the unallocated space in Disk Management. If there is no such unallocated space and you want to merge two partitions like C drive and D drive without data loss, it is recommended to apply AOMEI Partition Assistant Standard.

Besides merging partitions, AOMEI Partition Assistant Standard can help you create bootable media, migrate OS to SSD and so on. If you want to use advanced functions, e.g. convert dynamic disk to basic, recover lost partitions, convert MBR system hard drives to GPT and more, you can upgrade to the professional version.