Tethered and untethered are two of those words you might hear when you start doing your research into electric cars but are too polite to ask what it means. We’ve all been there, and luckily for you we are here to clear the air.

Boiling it down to the basics, tethered and untethered refers to electric car chargers. You might be asked to choose between them if you are ordering a home charger, or looking on a website at public chargers while planning a journey.

On a tethered charger, the cable is fixed at one end, usually onto the charge point. There are a couple of cars which have a cable tethered to them too – notably the Citroen Ami and the Renault Twizy.

An untethered connection has a Type 2 socket on the charger into which you can plug a cable. Both work perfectly well and will charge your electric car in the same time.

This is normal for slower AC public charge points, meaning you’ll need to bring your own cable to plug into them.

This makes them less convenient at home – unless you leave the cable locked in place semi-permanently – but some buyers prefer an untethered connection because it allows for different cable lengths to be attached to the charger, or for you to plug in different cables for different cars. For example, an old Nissan Leaf needs a Type 1 connector at the car’s end, but the later car has a Type 2. Going for an untethered charger means you are future proofed and can swap between cars.

As tethered chargers have the cable built in they are inevitably more expensive – reckon on between £50 to £100 more depending on the cable length.

Untethered cables are a little fiddlier at home

What about public chargers? 

As a rule of thumb, rapid chargers which supply 50kW or more from a DC unit will always have tethered cables, so there is no need to bring your own. This is because they need to be beefier than a conventional charger cable, so owners couldn't be expected to carry them around.

Anything below level this will usually be an AC supply and untethered, but there are some exceptions – notably Tesla’s network of destination chargers.

Can I swap from tethered to untethered at a later date? 

It is possible, but it’s not a DIY job. An engineer will need to come out and charge the parts. If you are unsure, the untethered option gives you the most flexibility and future proofing.

Tesla destination chargers are usually tethered