Cat6 vs Cat6a: Which Network Cable Should You Install?

Cat6a carries 10 gigabit Ethernet over the full 100 metre channel, while Cat6 only manages 10 gigabit up to about 55 metres in good conditions, and less where many cables are bundled together. That is the whole difference in one line. Cat6a is rated to 500 MHz against Cat6's 250 MHz, which is what lets it hold those speeds over distance, but it is thicker, stiffer and costs more to buy and install.

Cat6 vs Cat6a side by side

Both are twisted pair copper cables defined in the ANSI/TIA-568 and ISO/IEC 11801 cabling standards, and both use the same RJ45 style connectors. Here is how they compare in practice.

• Bandwidth: Cat6 is specified to 250 MHz; Cat6a to 500 MHz.

• Gigabit (1000BASE-T): both handle it over the full 100 metres.

• 10 gigabit (10GBASE-T): Cat6 up to about 55 metres at best; Cat6a over the full 100 metres.

• 2.5 and 5 gigabit: both handle these over 100 metres, and Cat5e usually can too.

• Size and handling: Cat6a is noticeably fatter and less flexible, so it needs more room in trunking, containment and back boxes, and a gentler bend radius.

• Cost: Cat6a cable, connectors and patch panels all cost more, and the installation takes longer.

The 100 metre figure is the whole channel: up to 90 metres of fixed cable from the patch panel to the wall outlet, plus up to 10 metres of patch leads at each end combined. Most homes never get near that. Many office floors do, and it is the first thing we measure when planning a data cable installation for a business.

Cat5e vs Cat6: is Cat5e still good enough?

Cat5e is rated to 100 MHz and runs gigabit Ethernet over 100 metres. Since the IEEE 802.3bz standard was approved in 2016, it can also carry 2.5 and 5 gigabit over up to 100 metres in most installations, so faster Wi-Fi access points can often reuse cable already in the walls.

So existing Cat5e is usually worth keeping if it tests well. For new work, though, the price gap between Cat5e and Cat6 is small compared with the labour of running the cable, and Cat6 gives more headroom. We would not install new Cat5e today unless we were extending an existing Cat5e system and matching it.

Shielded or unshielded?

Both Cat6 and Cat6a come unshielded (often labelled U/UTP) or with foil or braid screening (F/UTP, S/FTP and similar). Unshielded is lighter, cheaper and easier to terminate. Shielded cable resists interference better, which helps Cat6a hold 10 gigabit where lots of cables run bundled together or near electrical noise.

The catch is that a shielded system only works if it is shielded end to end: shielded connectors, shielded patch panel and the screen properly bonded. A shielded cable terminated into unshielded outlets gives you the cost and none of the benefit.

Whatever the category, insist on solid, pure copper conductors. The standards call for copper, and cheap copper clad aluminium (CCA) cable sold as "Cat6" does not meet them.

Which should you fit in a home?

For most homes, Cat6 is the sensible choice. Runs are short, usually well under 55 metres, so Cat6 can carry 10 gigabit if you ever need it, and it is easier to pull through existing walls and floors.

Cat6a is worth considering in a large house with long runs from a loft or garage cabinet, or if you are wiring during a renovation and want the most future headroom while the walls are open. Either way, the cable is the cheap part. The labour of getting it in is what you pay for, so do it once.

A few points we would plan for in any home:

• a run to every room where a TV, games console, desk or wireless access point will sit

• two outlets rather than one behind the TV and at the desk

• all runs brought back to one central point, not daisy-chained through switches in cupboards

• data cables kept apart from mains cables, not tied to them

Which should you fit in an office?

For a new office or a full refit, Cat6a is usually the right call. Horizontal runs on a commercial floor often exceed 55 metres, ceiling-mounted Wi-Fi access points are pushing past gigabit speeds, and the cabling is expected to outlast several generations of switches and computers.

Cat6 still makes sense in a small office where every run is short, or when adding a few points to an existing Cat6 system. Mixing categories on one link does not help: a Cat6a cable into Cat6 outlets performs as Cat6.

Whichever you choose, the installation matters as much as the label on the drum. Poor terminations, over-tight cable ties and bends that are too sharp can drag a link below its rated category. That is why a professional installation should end with every link tested and the results handed over, not just a check that the lights on the switch come on.

For an office, the cabling is also only one part of a wider system of patch panels, cabinets and labelling. Our guide to structured cabling explains how those pieces fit together.

Whether you need an electrician in Telford, Shifnal or Wolverhampton, we install data cabling for homes and businesses across the West Midlands. If you are planning a refit or an extension, get in touch and we will help you choose the right category before any cable goes in.

Network cable questions, answered

Can I plug Cat6a into equipment designed for Cat6 or Cat5e?

Yes. The connectors are the same and the standards are backward compatible. The link simply runs at the speed the weakest part allows.

Does Cat6a make my broadband faster?

Not on its own. Your internet speed is set by your broadband line. Better cabling helps moving files around inside the building and feeding Wi-Fi access points, where gigabit links can already be the limit.

Is Cat7 or Cat8 better?

For UK homes and offices, rarely worth it. Cat8 is only specified for links of around 30 metres, which suits equipment rooms rather than office floors, and Cat7 is not recognised by the TIA standards most network equipment is built around.