Fix Mac USB Transfer Very Slow

To Fix Mac USB Transfer Very Slow use a USB 3.0 adapter to enhance speeds or disable low-power mode.

Having trouble with slow USB transfer on your Mac? It’s a common issue experienced by many, causing tedious delays and frustration. This post offers comprehensive solutions to Fix Mac USB Transfer Very Slow, using proven methods backed by technical insights. Read on as we guide you step-by-step to accelerate your USB transfer speed in no time!

Quick Summary

  • Corrupted files and virus/malware infections can significantly slow down USB transfer speeds on Mac. Safely ejecting USB drives, using reliable power sources, and having antivirus software installed can help mitigate these issues.
  • The storage format of your USB drive can also impact transfer speed. Converting the file system to APFS (Apple File System) can improve compatibility and potentially enhance data transfer speeds.
  • While useful for quick file searches, spotlight indexing can consume valuable system resources and slow down USB transfers. Disabling Spotlight indexing specifically for your USB drive can free up resources and improve overall performance.
  • Using a high-quality USB cable and upgrading to a USB 3.0 adapter is crucial for optimal transfer speeds on Mac. USB 3.0 offers faster data transfer rates, backward compatibility with older versions, improved power efficiency, better performance with large files, and future-proofing compatibility with upcoming devices.

Common Causes of Slow USB Transfer on Mac

Several common causes for slow USB transfer on Mac include corrupted files, virus or malware infections, storage format issues, Spotlight indexing, and poor cable quality.

Corrupted files

Corrupted files can significantly slow down the USB transfer speed on your Mac. In such cases, the operating system struggles to read and write data from these defective files, resulting in a noticeable deceleration of the transfer process. These inconsistencies are often due to the unsafe removal of USB drives or sudden power cuts, disrupting ongoing transactions and leading to file corruption. To mitigate this issue, always eject your USB drive safely and use reliable power sources for your Mac. Fixing these corrupted files can help boost the performance and speed up data transfer to your USB on Mac considerably.

Virus or malware

Virus or malware infections can significantly impact the speed of USB transfers on your Mac. These malicious programs can cause system slowdowns, interfere with file transfers, and damage files. It’s important to have reliable antivirus software installed on your Mac and regularly scan for potential threats. By keeping your system clean from viruses and malware, you can ensure smoother and faster USB transfer speeds.

Storage format

The storage format of your USB drive can also impact the transfer speed on your Mac. Different file systems, such as FAT32 or exFAT, have different performance characteristics. For example, FAT32 is widely compatible but may have slower transfer speeds than other formats like APFS or NTFS. To fix the slow USB transfer speed caused by the storage format, it is recommended to convert your USB drive’s file system to APFS if you are using a newer macOS version. APFS (Apple File System) offers improved performance and compatibility with Mac systems. However, please note that converting the file system will erase all data on the USB drive, so back up any important files before proceeding.

Spotlight indexing

Spotlight indexing is a process on Mac that helps you quickly search for files and apps. However, it can also slow down your USB transfer speed. When Spotlight indexes your external drive, it reads and analyzes every file, which can take up valuable system resources. You can disable Spotlight indexing specifically for your USB drive to fix this issue. By doing so, you’ll free up system resources and improve the overall performance of your USB transfer speed on Mac. This simple step can make a significant difference in speeding up your file transfers to and from your USB drive. So if you’re experiencing slow USB transfer on your Mac, disabling Spotlight indexing could be the solution to boost efficiency and save valuable time.

Cable quality

A high-quality USB cable is crucial for fixing slow USB transfer on your Mac. A low-quality or damaged cable can significantly impact the speed and performance of your data transfer. Investing in a reliable, well-built cable ensures a stable connection between your Mac and the USB drive is important. A good quality cable will have better shielding and reduced signal interference, resulting in faster data transfer speeds. So make sure to check the condition of your USB cable and consider replacing it if necessary for smoother and faster file transfers on your Mac.

How to Fix Mac USB Transfer Very Slow

You can take several steps to fix slow USB transfer on your Mac. First, consider changing to a USB 3.0 adapter for faster data transfer speeds. Next, disable low-power mode in your Mac’s settings to ensure optimal power supply to the USB port. Additionally, turn off Spotlight indexing, which can slow down file transfers. Another solution is to convert the file system of your USB drive to APFS for improved performance. Lastly, deleting problematic Finder preference files can help resolve any speed issues with transferring files via USB on your Mac.

Change to a USB 3.0 adapter

To improve your Mac’s USB transfer speed, consider changing to a USB 3.0 adapter. This modern adapter is designed to offer faster data transfer rates than its predecessors. Change to a USB 3.0 adapter Upgrading to USB 3.0 allows you to use its enhanced technology and enjoy quicker file transfers.
  1. Faster transfer speeds: USB 3.0 provides much higher data transfer rates than USB 2.0 or earlier versions. With speeds up to ten times faster, you can save significant time when moving files between your Mac and external devices.
  2. Backward compatibility: While USB 3.0 is the latest standard, it is backwards compatible with older USB versions, allowing you to connect your existing devices without issues.
  3. Improved power efficiency: USB 3.0 adapters consume less power than previous versions, producing better battery life on portable devices such as laptops or MacBooks.
  4. Enhanced performance for large files: If you frequently work with large files like videos or high-resolution images, using a USB 3.0 adapter will significantly reduce the time required for data transfers.
  5. Future-proofing: As more devices adopt the USB 3.0 standard, upgrading now ensures compatibility with upcoming gadgets and peripherals.

Disable low-power mode

To further improve the USB transfer speed on your Mac, one effective step is to disable low-power mode. This feature reduces power consumption on your device but can also limit your USB ports’ performance. Disable low-power mode Follow these steps to disable low-power mode:
  1. Click on the Apple menu in your screen’s top-left corner.
  2. Select “System Preferences” from the drop-down menu.
  3. In the System Preferences window, choose “Energy Saver.”
  4. In the Energy Saver tab, uncheck the option for “Put hard disks to sleep when possible.”
  5. Additionally, adjust the settings under “Computer Sleep” and “Display Sleep” by moving the slider towards “Never” or longer duration.
  6. Close the System Preferences window.

Turn off Spotlight indexing

To fix the slow USB transfer speed on your Mac, one effective solution is to turn off Spotlight indexing. Spotlight indexing is a feature that allows you to search for files and folders on your Mac quickly. However, it can consume system resources and potentially slow file transfer speeds. Here’s how to turn it off:
  1. Open “System Preferences” from the Apple menu or by clicking its icon in the Dock.
  2. Click on “Spotlight.”
  3. In the “Search Results” tab, uncheck all the checkboxes for categories you don’t use often or need for searching.
  4. Click on the “Privacy” tab.
  5. Click the “+” button and select the USB drive with which you are experiencing slow transfers.
  6. Click “Choose” to add it to the Privacy list.
  7. Close System Preferences.

Convert USB file system to APFS

To improve the slow USB transfer speed on your Mac, one effective solution is to convert the USB file system to APFS. APFS (Apple File System) is the default file system used in macOS High Sierra and later versions. It offers several advantages over older file systems, including improved performance and enhanced data integrity.
  1. Connect your USB drive to your Mac.
  2. Open Disk Utility by going to Finder, selecting “Applications,” then “Utilities,” and clicking on “Disk Utility.”
  3. In Disk Utility, select your USB drive on the left-hand side.
  4. Click on the “Erase” tab at the top of the window.
  5. Choose a new name for your USB drive if desired.
  6. Under “Format,” select “APFS” from the drop-down menu.
  7. Check that the scheme is set to “GUID Partition Map” for Intel-based Macs or “Apple Silicon” for M1-based Macs.
  8. Click the “Erase” button to format your USB drive as APFS.
  9. Once formatting is complete, you can safely eject and disconnect your USB drive from your Mac.

Delete problematic Finder preference files

To further improve the slow USB transfer speed on your Mac, you can try deleting problematic Finder preference files. These files may be causing conflicts or errors that are hindering the performance of your USB transfer. Here’s how to do it:
  1. Quit the Finder application by clicking on the Apple menu and selecting “Force Quit.”
  2. Select Finder in the Force Quit Applications window and click the “Relaunch” button.
  3. Open a new Finder window by clicking on the desktop or using the keyboard shortcut Command + N.
  4. Click “Go” in the top menu bar and select “Go to Folder.”
  5. In the Go to Folder window, type “~/Library/Preferences” (without quotes) and click on the “Go” button.
  6. Locate and select the following preference files related to Finder:
  7. Move these files to the Trash by dragging them or right-clicking and selecting “Move to Trash.”
  8. Empty the Trash by right-clicking on its icon in the Dock and selecting “Empty Trash.”

Other Tips to Improve USB Transfer Speed on Mac

Use high-quality USB cables for optimal data transfer. Low-quality cables can result in poor connectivity and slower transfer speeds. Additionally, avoid transferring large files simultaneously, which can overload the system and decrease transfer speed. Finally, ensure your USB drive and Mac are kept clean and optimized to maximize performance.

Use high-quality USB cables

The quality of USB cables can significantly impact the transfer speed on your Mac. High-quality USB cables ensure better data transmission and minimise signal loss, resulting in faster transfer speeds. Cheap or faulty cables may not provide a stable connection, leading to slower file transfers. Investing in reliable and well-made USB cables can make a noticeable difference in improving the overall speed and efficiency of transferring files between your Mac and external devices.

Avoid transferring large files at once

Transferring large files all at once can significantly slow down the USB transfer speed on your Mac. Attempting to copy a large file requires more time and resources for the system to complete the transfer. This can lead to slower performance overall. Breaking up larger files into smaller chunks and transferring them individually is best to optimise your USB transfer speed. Transferring smaller portions of the file simultaneously allows your Mac to process each part more efficiently, resulting in faster overall transfer speeds. Transferring large files in smaller increments also reduces the risk of encountering errors or corruption. This ensures that each data segment is transferred successfully without loss or damage.

Keep the USB drive and Mac clean and optimized

To ensure optimal USB transfer speed on your Mac, it’s important to keep both the USB drive and your Mac clean and optimized. Start by regularly cleaning out unnecessary files or folders from your USB drive. This will free up valuable storage space and improve data access speeds during transfers. Additionally, keeping your Mac clean is equally crucial. Regularly run disk cleanup utilities to remove temporary files, cache data, and other unnecessary system clutter that can hinder performance. You can also optimize your Mac by regularly updating its operating system and software to exploit the latest bug fixes and performance enhancements.


In conclusion, experiencing slow USB transfer on your Mac can be frustrating, but various solutions are available to help improve the speed. You can significantly enhance your Mac’s USB transfer performance by following the tips and techniques outlined in this blog, such as using a USB 3.0 adapter, disabling low-power mode, and optimizing your storage format. Don’t let slow file transfers hold you back – take control and enjoy faster data transfer speeds on your Mac today!


1. Why is my Mac USB transfer so slow?

There could be several reasons for slow USB transfers on your Mac, including outdated software or drivers, a faulty USB port, insufficient power supply to the connected device, or too many files or large file sizes being transferred.

2. How can I fix the slow USB transfer speed on my Mac?

To improve USB transfer speed on your Mac, you can try the following solutions: ensure that your operating system and drivers are up to date, use a different USB port or cable for the connection, connect directly to a powered hub if using multiple devices, remove unnecessary files from your storage devices to free up space, and consider using third-party software or utilities designed to optimize USB performance.

3. Can I adjust software settings to enhance the USB transfer speed on my Mac?

Yes! You can adjust a few settings to increase USB transfer speed on your Mac potentially. You can try adjusting energy-saving settings, such as disabling sleep mode during data transfers and enabling faster disk performance by disabling FileVault encryption.

4. What should I do if none of the troubleshooting steps work?

Suppose none of the troubleshooting steps mentioned above improves the slow USB transfer speed on your Mac. In that case, consulting with an Apple-authorized service provider or contacting Apple Support for further assistance may be helpful. They will have more advanced diagnostic tools and expertise to identify any underlying hardware issues causing the problem.