Partition a Thumb Drive [Windows, macOS & Ubuntu Linux]

A thumb drive, also called a USB flash drive, normally appears as one storage area when you connect it to a computer. However, you can divide that storage into multiple partitions, with each partition acting like a separate storage volume.

Partitioning can be useful when you want to keep different types of files separated, create a dedicated bootable area, or use one USB drive for different purposes. The process is slightly different on Windows, macOS, and Ubuntu Linux, but the basic idea is the same.

Before you begin, remember that partitioning can erase data when partitions are deleted, recreated, or reformatted. Back up anything important on the thumb drive before following these steps.

Table of Contents

Partition a Thumb Drive [Full Guide for Windows, macOS & Ubuntu Linux]

You can partition a USB flash drive using the operating system’s disk management tools. The following methods explain the process from beginning to end and are written for users who have never partitioned a drive before.

Windows

Windows provides Disk Management, which is the easiest built-in way to manage partitions on a USB drive. The important thing to understand is that Windows cannot normally create a second partition from free space if the existing partition occupies the entire drive. You may need to shrink the existing volume first.

Step 1: Back Up the Thumb Drive

Connect your thumb drive to your Windows PC and open File Explorer. Select This PC and locate the USB drive under Devices and drives.

Open the drive and copy any important documents, photos, videos, or other files to another location. This step is essential because changing partitions can result in data loss.

Once your backup is complete, close any applications that are accessing files on the USB drive.

Step 2: Open Disk Management

Right-click the Start button and select Disk Management. You can also press Windows + X and choose Disk Management from the menu.

A new window will display your computer’s disks and their partitions. You may see your internal SSD or hard drive as well as the connected USB drive.

Pay close attention to the drive capacity and drive number. Do not select your Windows system drive by mistake.

Step 3: Identify the Thumb Drive

Find the USB drive in the lower section of Disk Management. Compare its displayed capacity with the actual capacity of your thumb drive.

For example, a drive advertised as 64 GB may appear somewhat smaller in Windows. This is normal.

Once you are certain you have selected the correct USB disk, you can continue.

Step 4: Shrink the Existing Partition

If the USB drive already contains one large partition, right-click that partition and select Shrink Volume.

Windows will calculate how much space can be reduced. Enter the amount of space you want to remove from the existing partition.

For example, if you want approximately 20 GB for a second partition, enter an appropriate amount in the shrink dialog. Remember that Windows asks for the amount in MB, not GB.

Click Shrink and wait for Windows to finish. You should now see Unallocated space beside the original partition.

Step 5: Create the Second Partition

Right-click the Unallocated space and select New Simple Volume.

The New Simple Volume Wizard will appear. Click Next, specify the size of the new partition, and click Next again.

You can allow Windows to assign a drive letter automatically, or select one yourself.

Step 6: Format the New Partition

Choose a file system for the new partition. exFAT is a practical choice when you need to move files between Windows and macOS because it supports large files and is widely compatible.

Enter a recognizable Volume Label, such as USB-Data, and continue through the wizard.

Click Finish to create and format the partition.

Afterward, open File Explorer > This PC. Your USB drive should now show multiple volumes.

macOS

macOS uses Disk Utility to manage USB partitions. The interface is different from Windows, but the overall process is straightforward.

Step 7: Open Disk Utility

Connect the thumb drive to your Mac. Open Disk Utility by pressing Command + Space, typing Disk Utility, and pressing Enter.

In Disk Utility, select View > Show All Devices. This makes it easier to distinguish the physical USB device from the volumes stored on it.

Step 8: Select the Physical USB Drive

In the left sidebar, locate your thumb drive and select the physical device, not just one of its existing volumes.

Check its name and capacity carefully. Selecting the wrong device could cause serious data loss.

If the drive contains important files, make sure you have already backed them up.

Step 9: Create a Partition

With the USB device selected, click Partition in the Disk Utility toolbar.

A partition diagram will appear. Click the Add button to create another partition.

Enter a name for the new partition and specify its size. You can adjust the partition size by entering the desired value or dragging the partition controls where available.

Step 10: Choose the Format

Select an appropriate file system for the partition.

For use exclusively with Mac computers, APFS can be appropriate for supported macOS workflows. For sharing files between different operating systems, exFAT is often a more convenient option.

Confirm the partition operation and allow Disk Utility to complete the process.

Step 11: Verify the Partitions

After the operation finishes, the new partitions should appear in Disk Utility and usually in Finder.

Open each partition and verify that it can be accessed normally. If you intend to use the thumb drive on another operating system, test it there as well.

Ubuntu Linux

Ubuntu provides Disks and GParted for partition management. Disks is commonly available by default, while GParted may need to be installed separately.

Step 12: Open the Disks Utility

Connect the USB thumb drive to your Ubuntu computer.

Open the application menu and search for Disks. Launch the utility and look through the list of storage devices.

Select your thumb drive by checking its capacity and device name. Be extremely careful not to select the internal drive containing Ubuntu.

Step 13: Unmount the USB Partition

Before modifying a partition, Ubuntu may require it to be unmounted.

Select the USB partition and click the unmount button, usually represented by a stop or eject-style control.

Do not physically remove the USB drive while Ubuntu is working with it.

Step 14: Resize the Existing Partition

Select the partition you want to resize and open its partition options. Choose the option to resize the partition.

Reduce its size to create unused space for another partition. The exact controls can vary depending on the Ubuntu version and file system.

Apply the change and wait for the operation to finish.

Step 15: Create a New Partition

Once you have unallocated space, select it and choose the option to create a new partition.

Specify the desired size and select a file system.

For general file sharing between Windows, macOS, and Linux, exFAT can be a useful choice. For Linux-specific use, ext4 is another common option.

Give the partition a meaningful label and confirm the operation.

Step 16: Check the USB Drive

After the partitioning operation completes, Ubuntu should recognize the new partition.

Open Files and check the sidebar for the USB volumes. Click each partition to confirm that it mounts correctly.

If necessary, safely eject the USB drive and reconnect it to verify that the partitions remain available.

Faqs

Can I partition a USB thumb drive without losing data?

Sometimes, yes. If you shrink an existing partition without deleting it, the existing files may remain intact. However, partition operations always carry some risk, so creating a complete backup first is strongly recommended.

How many partitions can a thumb drive have?

The number depends on the partitioning scheme, operating system, file system, and how the USB drive is configured. Most everyday users only need two or three partitions.

Which file system should I use?

Choose exFAT when you want broad compatibility and need to store large files. Choose NTFS for Windows-focused use, APFS for Mac-focused storage, or ext4 for Linux-focused use.

Why is my second USB partition not appearing?

The partition may not have been formatted, mounted, or assigned a drive letter. On Windows, check Disk Management. On macOS, check Disk Utility. On Ubuntu, check Disks or Files.

Can I use one partition for Windows and another for Linux?

Yes. A USB drive can contain multiple partitions with different file systems. However, compatibility depends on the operating system and how each partition is formatted.

Does partitioning make a USB drive faster?

No. Partitioning primarily changes how the available storage is organized. It does not normally increase the physical read or write speed of the thumb drive.

Should I use MBR or GPT?

For a normal data USB drive, either may work depending on your compatibility requirements. GPT is the modern partitioning scheme and is generally preferable for newer systems, while MBR can provide compatibility with older hardware and software.

Summary

Partitioning a thumb drive lets you divide one USB device into multiple independent storage areas. On Windows, you can use Disk Management. On macOS, Disk Utility provides the required controls. On Ubuntu, the Disks utility offers a beginner-friendly way to resize and create partitions.

The most important rule is to identify the correct USB drive before making changes. Always back up important data, double-check the drive capacity, and avoid modifying your computer’s internal system disk.

Once the partitions are created and formatted correctly, each one can be used for a different purpose while remaining part of the same physical thumb drive.