Why are uploads speeds slow?

For many people in the UK, download speeds are either acceptable or very good. However, upload speeds can still leave you tapping your feet. Here’s why.

In the UK, the vast majority of homes get broadband via ADSL, with fewer using the faster fibre-optic services offered by Virgin, BT and others. See also: Best broadband, cheapest broadband, fastest broadband: UK ISPs rated

ADSL stands for Asymmetric (or Asynchronous) Digital Subscriber Line. Asymmetric is the operative word here, as it means that download and upload speeds are not the same.

ADSL relies on the old copper wire running to your home for your telephone, meaning broadband data has to share the cable with phone calls. Priority is given to downloads on the limited bandwidth, meaning uploads are much slower.

Why are uploads speeds slow?

Typically you can expect anything up to 20Mbps for downloads on ADSL, with around 10 percent of that as an upload speed. Those are maximums, though, and if you don’t live on top of your local exchange, you might see much lower figures.

To find out what you should be getting, head to the SamKnows website where you can find out which broadband services are available, along with their estimated download and upload rates.

Why are uploads speeds slow?

If you live far from an exchange, check if you can receive broadband via cable or fibre. Depending on where you live you may have a fibre-optic cable already installed in the pavement outsite, and you can sign up to a Virgin package which entails the cable being extended inside your home.

An alternative is BT’s Infinity, which works slightly differently. Instead of the fibre-optic cable running right to your house, it extends only as far as your local cabinet, which could be at the end of your road. This is why it’s called FTTC – fibre to the cabinet. For the rest of the distance, the existing copper cables are used, but you’ll still see much better speeds than via ADSL. See also: BT Home Hub 5 review

For example, I live several miles from my local exchange in Greater London. Via ADSL I would get around 1.5Mbps download and 0.5Mbps upload. However, via BT Infinity, I get roughly 40Mbps download speeds and 10-12Mbps uploads. Find out how fast your upload and download speeds could be on BT's site.

Opting for Virgin would net me ‘up to’ 152Mbps download speeds and 12Mbps uploads. You can check your postcode on Virgin’s site Virgin's website to see whether you’re in a cabled street or not.

Upload speeds on fibre / cable connections are limited in a similar way to ADSL. Most people download considerably more than they upload, so it makes sense to prioritise downloads rather than capping them in order to free up bandwidth for uploads.