USB Extension Cable

Everything You Need to Know About USB-A and USB-C Extension Cables

Written by: Pete Luckhurst

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Time to read 5 min

USB extension cables are a handy solution for extending the reach of your devices, whether you’re connecting a webcam, printer, smartphone, or external hard drive. In this guide, we’ll explain the key differences between USB-A and USB-C extension cables, how to use them effectively, and what to watch out for to maintain optimal performance.


Can a USB-A or USB-C Cable Be Extended?

Yes, both USB-A and USB-C cables can be extended using compatible extension cables. USB-A is the traditional rectangular connector used for a wide range of devices including keyboards, mice, and external storage. USB-C is a newer, reversible connector used on many modern smartphones, laptops, and tablets.


Whether you need to extend a USB-A port on a desktop PC or a USB-C port on a MacBook, there are reliable options available. Extension cables are available in various lengths and specifications. However, choosing the right type is crucial to avoid issues such as power loss or signal degradation.


How to Extend a USB-A or USB-C Cable

There are several ways to extend a USB cable:

1. USB Extension Cable

This is the most straightforward method. Simply plug the male end of the extension cable into your device’s USB port and then connect your original cable to the female end. Shop USB-A Extension Cables or USB-C Extension Cables.

2. USB Coupler/Joiner

A USB coupler allows two USB cables to be joined together. This is useful if you already have two shorter cables.

3. Active USB Extension Cable

Also known as a USB repeater cable, an active extension cable contains electronics that boost the signal. This is ideal for longer distances and helps prevent data loss.

4. USB Hub with Long Cable

Some powered USB hubs come with longer built-in cables. These are especially useful for setting up workstations or charging multiple devices at once.


How Long Can a USB Extension Cable Be Before the Signal Degrades?

The maximum effective length of a USB cable depends on the version of USB in use:

  • USB 2.0: Up to 5 metres (about 16 feet)

  • USB 3.0/3.1/3.2: Typically around 3 metres (about 9.8 feet)

  • USB4/Thunderbolt 3/4: Varies depending on cable quality and type, often maxing out around 0.8 to 2 metres for passive cables

For longer runs, active extension cables or USB over Ethernet solutions are recommended to maintain performance and prevent data loss.

USB-A vs USB-C Supported Cable Lengths

While both USB-A and USB-C cables can be extended, the maximum usable length is influenced more by the USB version and features (such as data speed and power delivery) than by the connector type itself.


  • USB-A: Length guidelines are more consistent. For example, USB 2.0 can go up to 5 metres, and USB 3.0 is usually capped around 3 metres unless using active cables.

  • USB-C: Supports more versions and features, making length limits more variable. Passive USB-C 3.1 Gen 2 cables (supporting 10Gbps data transfer) are typically limited to 1 metre to ensure signal integrity. USB4 and Thunderbolt 4 cables are often limited to 0.8 metres for full-speed operation, unless specially designed as active cables.


However, longer high-quality USB-C 3.2 Gen 2 cables do exist and can support 10Gbps speeds over greater distances. For example, Maplin’s 3-metre USB-C extension cable supports USB 3.2, 10Gbps data transfer, and up to 100W Power Delivery. This cable is available in 1, 2, and 3 metre lengths, providing greater flexibility without compromising speed or performance.

In short, USB-C cables are more sensitive to length when high data transfer speeds or Power Delivery (PD) are involved. Always check the specifications of your devices and cables when planning an extension.


The Safety of USB Extension Cables

Yes, USB extension cables are generally safe to use provided you follow a few basic guidelines:

  • Use high-quality, certified cables from reputable manufacturers.

  • Avoid daisy-chaining multiple passive cables, as this increases the risk of signal degradation.

  • Check power requirements: USB-powered devices like external hard drives or webcams may not function correctly if the voltage drops over long distances.

  • Use active extension cables for longer distances or power-hungry devices.

Safety issues typically arise only when low-quality or excessively long cables are used.


Do USB Extension Cables Affect Performance?

They can, depending on cable quality, length, and the type of USB interface:

  • Data Transfer Speed: A low-quality or overly long extension cable can reduce the maximum achievable data transfer rate.

  • Power Delivery: Voltage drop over long distances may result in insufficient power delivery, causing devices to disconnect or malfunction.

  • Device Compatibility: Some USB 3.0 and USB-C devices may require high-speed connections that cheap or older extension cables can't support.

To ensure optimal performance:

  • Use short, certified cables for high-speed data transfer

  • Choose active extension cables for lengths over 3 metres

  • For USB-C, verify that the cable supports Power Delivery (PD) and high-speed data if needed


Additional Tips for Choosing the Right USB Extension Cable

1. Check USB Version Compatibility

USB-A and USB-C cables come in multiple versions (e.g., USB 2.0, 3.0, 3.1). Match the extension cable to the version of the devices you are using to avoid bottlenecks.

2. Look for Shielding and Build Quality

Well-shielded cables reduce electromagnetic interference (EMI) and crosstalk, ensuring more reliable connections.

3. Consider a Powered Hub for Multiple Devices

If you’re extending a USB connection to use with multiple peripherals, a powered USB hub can help distribute enough current to each device without overloading the port.

4. Verify Support for Video and Audio (for USB-C)

If you’re extending a USB-C port used for video output (e.g., to an external monitor via DisplayPort or HDMI over USB-C), make sure the cable explicitly supports alternate modes like DisplayPort Alt Mode.


Summary

USB-A and USB-C extension cables are practical tools that help overcome the limitations of short built-in cables, making your setup more flexible and ergonomic. However, they’re not all created equal. For the best results, choose high-quality, version-compatible, and appropriately long cables—especially if you’re dealing with high-speed data transfer or power-hungry devices.

Explore Maplin’s full range of USB-A and USB-C extension cables to find the right solution for your tech needs. With the right extension cable, you can boost both convenience and performance without compromise.

About the author

Pete Luckhurst is a Website Manager at Maplin.

After getting an early start in the world of computing with C64 & Amiga computers, Pete now spends much of his spare time in PC VR and dabbling in game development. He also has a strong interest in film, photography and music.

Among other endeavours, he previously worked in a Maplin store, so it was a no-brainer when the opportunity arose to work on the modern incarnation of Maplin online. Besides writing for the blog, Pete works alongside the Maplin team to help keep the online store running smoothly.

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