Tethered vs Untethered EV Charging: Do You Need a Separate Cable?

When you get a home wallbox installed, one of the first decisions the installer will ask about is whether you want a tethered or untethered unit. If you have already made that call and now you are trying to work out whether you need to buy a separate cable, the answer depends entirely on which type you have. This guide explains the difference, lists which popular wallboxes fall into each category, and tells you exactly which cable to buy if you need one.

What Does Tethered Mean?

A tethered EV charger has a cable permanently attached to the unit. The cable is built in, typically three to ten metres long, and cannot be removed or swapped. You simply uncoil the cable, plug the car end into your vehicle, and charging begins. There is nothing extra to buy and nothing extra to store.

The main limitation is flexibility. If you change to a car with a different inlet type, or if you decide you want a longer cable, you cannot swap it out without replacing the wallbox unit or having an electrician modify the installation.

What Does Untethered Mean?

An untethered charger, sometimes called a socketed charger, has a standard Type 2 socket on the front of the unit rather than a fixed cable. You plug a separate charging cable into the socket, connect the other end to your car, and charging begins. When you are done, you unplug the cable and store it.

Untethered wallboxes are the dominant choice in the UK market right now. They give you flexibility: you can use any compatible Type 2 cable, switch cable lengths, and adapt easily if you change vehicles. Most smart wallboxes launched in the last four years are untethered by default, with tethered versions available as an add-on or a separate model in the range.

Which Wallboxes Are Untethered?

If you are not sure which type your wallbox is, look at the front of the unit. A socket on the face means untethered: you need a cable. A cable hanging from the unit means tethered: you do not.

What Type of Cable Do You Need for an Untethered Wallbox?

For the vast majority of UK setups, you need a Type 2 to Type 2 cable. The Type 2 end plugs into the wallbox socket and the other Type 2 end plugs into your car. This covers essentially all modern EVs and PHEVs registered in the UK, including every Tesla, BMW, Volkswagen, Audi, Hyundai, Kia, Renault, Peugeot, and Mercedes model sold with a European-spec inlet.

A small number of older vehicles use a Type 1 inlet: early Nissan Leaf models (pre-2018), the first-generation Mitsubishi Outlander PHEV, and a handful of early Chevrolet Volt imports. If your car has a round, five-pin inlet rather than the oval, seven-pin Type 2 port, you need a Type 2 to Type 1 cable. Our vehicle lookup tool will confirm which connector your car needs in seconds.

What Power Rating Cable Do You Need?

Most untethered home wallboxes output 7.4 kW on a single-phase supply, which is the standard UK residential connection. A 7.4 kW cable is the right choice for almost every home setup. If your property has a three-phase supply and your wallbox is rated at 22 kW, you need a 22 kW cable and a car that supports three-phase AC charging.

Not sure whether to go for 7.4 kW or 22 kW? See our full guide: 7.4 kW vs 22 kW EV charging cables explained.

What Length Cable Should You Buy?

Measure the distance from your wallbox socket to where your car's charge port will sit when parked. Add one to two metres of slack for comfortable plugging and unplugging without stretching. Most UK home installs work well with a five-metre cable. Large garages or long driveways typically need seven and a half to ten metres.

View our full range of Type 2 to Type 2 charging cables in five, seven and a half, and ten metre lengths, and use the cable finder to match the right specification to your car and wallbox.

Pros and Cons of Each Type