Windows 10 File Copy to USB Very Slow: Getting Faster Transfers to Flash Drives

You drag a folder onto a flash drive, and the progress window shows a speed of a few megabytes per second, with hours remaining. When a Windows 10 file copy to USB very slow turns a quick backup into slot online an afternoon’s wait, the drive often gets the blame.

Sometimes the drive really is slow. Many cheap flash drives write far more slowly than they read. But Windows settings, the port you use, and the type of files being copied all make a large difference.

A USB 3.0 drive plugged into a USB 2.0 port, for example, can run several times slower than it should.

Checking these factors usually reveals a quick improvement.

Possible Causes

USB copies crawl for these reasons:

• The drive is plugged into a USB 2.0 port, or into a hub.
• The copy contains thousands of small files rather than a few large ones.
• The drive is formatted as FAT32 and is old, cheap, or nearly full.
• Antivirus software scans each file as it is written.

Write speeds often start fast and then drop sharply on budget drives once their internal cache fills.

Quick Fixes to Try First

Use the fastest connection.

1. Plug the drive directly into a USB 3.0 port, usually marked with a blue insert or “SS.”
2. Avoid unpowered hubs and front-panel ports with long internal cables on desktops.
3. Copy one large file to compare speeds with copying many small files.
4. Close other programs that use the drive.
5. Restart the PC and try again.

If one large file copies quickly but many small files are slow, compress the folder into a ZIP file before copying.

Advanced Steps for Stubborn Cases

Adjust the drive’s settings.

1. Open Device Manager, expand Disk drives, right-click the USB drive, and choose Properties.
2. On the Policies tab, select “Better performance.” You must then always use “Safely Remove Hardware” before unplugging.
3. Back up the drive and format it as exFAT or NTFS, which handle large files better than FAT32.
4. Pause antivirus scanning briefly and compare speeds.
5. Test the drive’s speed on another computer to confirm whether the drive itself is slow.

Before You Go Further: Keep Your Files Safe

“Better performance” mode caches data, so unplugging without safe removal can corrupt files. Formatting erases the drive, so back it up first. Very slow or failing drives should be replaced.

Conclusion

Slow USB copies are usually caused by ports, file types, or drive quality. Use USB 3.0 ports, bundle small files, and enable better performance mode with safe removal.

When buying new flash drives, look for models that list write speeds, not just read speeds, since write speed matters most for copying files onto the drive.