This part will show you merge partitions in Windows 11 in two different ways. One is to merge partitions through Windows built-in tool Disk Management, and the other is to use third-party software. You can choose one to use according to your disk’s current status.
Best Ways To Merge & Manage Disk Partition in Windows 11
Method 1. Merge partitions in Windows 11 via Disk Management
Windows Disk Management can help you merge partitions through Extend Volume, but this feature will only be enabled when there is unallocated space on the right side of the target partition. Otherwise, it will be grayed out.
As shown in the figure, if you want to extend the C drive, the D drive must be unallocated space. If it is not, you can delete it to get unallocated space.
Step 1. Open Disk Management in Windows 11 (You can click the Windows icon on the desktop and select Disk Management).
Step 2. Locate the two partitions you want to merge, and then delete one partition. For example, to combine a C drive and a D drive, you have to delete the D drive. Right-click on the D partition and select “Delete Volume”.
Step 3. Next, right-click on the system partition and select the "Extend Volume" option.
Step 4. Follow the Extend Volume Wizard and accept the default options to merge two partitions in Windows 11
Method 2. Merge partitions in Windows 11 by free alternative software
Did you see it? Disk Management can merge partitions only when adjacent partitions are deleted. If you want to merge partitions without losing data, then I highly recommend you to use a free partition management software.
What’s more, it also has more functions that are popular with users, such as Resize Partition, Creates Partition, and more. Please download the demo version to see how to merge combined partitions in Windows 11/10/8/7/Vista/XP.
AOMEI Partition Assistant Standard
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Step 1. Install and run it. Right-click the partition you need to merge (e.g. Partition D) and choose Merge Partitions. 
Step 2. Choose the partition that you need to be merged and click OK.
Step 3. In the main interface, after confirming operation, click Apply and Proceed to commit it.
