The cable length options stare back at you from the product page: 5m, 7m, 10m, 15m. Pick too short and you’re stretching it across the driveway like a tripwire, or finding out at a public charger that you can’t reach the socket from a normal bay. Pick too long and you’re carrying kilograms of cable you never uncoil, paying more than you need to. The good news is there is a correct method for choosing, and it takes about two minutes to apply.
Why cable length matters more than most buyers expect
Your charging cable connects two things: a socket on a wall (your wallbox or the public post) and a charge port on your car. The distance between those two points is not fixed. It depends on where the socket is mounted, where you park, and where your charge port is on the car.
That last variable catches people out more than any other. Charge port positions vary significantly between EV models. The Tesla Model 3 has its port on the rear left. The Hyundai Ioniq 5 has it on the rear right. The BMW iX puts it on the front right. The MG4 uses the rear left. Park nose-in with a rear-right port and a wallbox on the right wall, and your cable needs to travel the full length and width of the car before reaching the socket.
This is why buying “whichever looks right” or copying what someone on a forum recommends often fails. Your setup is specific. The measuring method below makes it specific to you.
The measuring method: how to get your number before you buy
This is the only reliable approach. Do it before you buy anything.
Step 1: Stand at your wallbox (or mark where it will be installed). Note the height of the socket above ground. Most wallboxes sit at 1-1.5m.
Step 2: Run a tape measure or a length of rope from the socket, down to ground level, then along the ground to your car’s charge port. Do this with the car parked in every position you realistically use: nose-in, reversed, offset left, offset right.
Step 3: Note the longest distance you measured. That is your baseline.
Step 4: Add one metre of slack. A cable that reaches exactly, with no drape, strains both the wallbox socket and your car’s charge port connector. It is also a trip hazard. One metre of slack is the minimum; it allows the cable to drape naturally and removes tension from both ends.
Step 5: Round up to the next standard length. Standard lengths are 5m, 7m, 10m, 15m, 20m, 25m. If your measured distance plus slack comes to 6.2m, buy a 7m cable.
- Top-down view of a UK driveway. Wallbox mounted on side wall at 1.2m height. Car parked nose-in. Red dashed line showing cable route: down from wallbox (1.2m vertical), along ground, up to car charge port. Two scenarios side by side: (A) charge port on near side (short route, ~3-4m), (B) charge port on far side (long route, ~6-7m, cable runs across car width). Annotate add 1m slack. Callout: Measure every park position; use the longest result.
The standard lengths and what each is for
5 metres
A 5m cable works if your wallbox is mounted directly beside your parking position and your charge port is on the near side of the car. That is a narrow set of conditions.
In practice, 5m gives you approximately 3-3.5m of usable horizontal reach once you account for the wallbox height and the drop to ground level. If your charge port is on the far side of the car, which is common for rear-right ports on cars like the Hyundai Ioniq 5, you are likely to fall short with 5m.
Buy 5m if: Your wallbox is immediately beside your parking spot, you have measured and confirmed it reaches your port, and you only ever charge at home.
7 metres
Seven metres is the right cable for the largest number of UK EV owners. It gives approximately 5-6m of usable horizontal reach, which handles most single-car driveway configurations regardless of port position, and covers every public AC destination charger scenario comfortably.
It is the length we ship most often, and in our own returns data, dissatisfaction with cable length almost always runs one direction: buyers who went shorter and found themselves short at a public charger.
Buy 7m if: You have a standard single-car driveway, you use public AC destination chargers occasionally, or you are unsure and don’t want to measure.
10 metres
Ten metres makes sense in specific situations: a long driveway where the wallbox is at the far end; a detached garage where the socket is inside and the car parks outside; on-street parking where you need extra flexibility for bay position; or any situation where your measured distance (plus slack) exceeds 7m.
Buy 10m if: Your measured distance exceeds 6m, you charge on-street regularly, or you have an outbuilding charger with a long run to where you park. Our dedicated 10m guide walks through every scenario where 10m beats 7m.
The port-side factor: front, rear, or side charge port
Port position is one of the biggest variables in cable length selection, and the one most buyers don’t account for when buying their first cable.
- Top-down car outline (generic 5-door hatchback). Label four port positions: Front-left (e.g. Renault Zoe), Rear-left (Tesla Model 3/Y, MG4, Volkswagen ID.4), Rear-right (Hyundai Ioniq 5, some BMW), Front-right (BMW iX). For each position, show cable routing arrow and note: Front near-side = no extra length needed; Rear near-side = add car length ~4.5m; Far rear = add car length + car width ~6.5m; Front far-side = add car width ~2m. Caption: Port on the far rear requires the most cable, so measure carefully before buying.
The practical rule: if your charge port is on the same side as the wallbox and your car is parked nose-in, a shorter cable will do. If your charge port is on the opposite side, or at the rear of the car when you park nose-in, you need substantially more reach than the raw driveway distance suggests.
Does cable length affect charging speed? Voltage drop explained
Longer cables have slightly more electrical resistance, which causes a small voltage drop under load. Whether this matters in practice depends on the cable length and conductor cross-section.
For a quality 32A Type 2 cable using 6mm² copper conductors, the standard for full-rated home charging cables, the voltage drop at 7.4kW (32A) is approximately:
- 5m cable: ~0.5% voltage drop
- 7m cable: ~0.7% voltage drop
- 10m cable: ~1.5% voltage drop
- 15m cable: ~2.5% voltage drop
- 20m cable: ~3.5% voltage drop
BS 7671:2018+A2:2022 (IET Wiring Regulations), Section 722, specifies voltage drop limits for EV charging circuits. A quality cable at lengths up to 10m stays comfortably within those limits using 6mm² conductors. At 15-25m, conductor sizing becomes important. This is why longer cables should be specified at higher gauge, not simply be longer versions of short cables.
The practical upshot: voltage drop at 5-10m is not a meaningful factor in your charging speed. At 15m and above, it is worth checking the conductor specification before buying.
- Dual-axis chart. X-axis: Cable length (5m, 7m, 10m, 15m, 20m). Left Y-axis (bars, blue): Total cable weight in kg, 5m: 2.5kg, 7m: 3.5kg, 10m: 5.0kg, 15m: 7.5kg, 20m: 10.0kg. Right Y-axis (line, orange): Voltage drop % at 7.4kW (32A, 6mm² conductor), 5m: 0.5%, 7m: 0.7%, 10m: 1.5%, 15m: 2.5%, 20m: 3.5%. Add horizontal dashed caution threshold line at 3% on voltage drop axis. Annotate 10m position as most people's practical upper limit for daily carry.
Weight per metre: what you’re carrying
Weight follows length directly. A 32A Type 2 charging cable weighs approximately 0.5-0.6kg per metre of completed cable. That gives you:
| Length | Approximate weight |
|---|---|
| 5m | ~2.5kg |
| 7m | ~3.0-3.5kg |
| 10m | ~4.5-5.0kg |
| 15m | ~7.5kg |
| 20m | ~10kg |
A 7m cable at ~3.5kg is barely perceptible in the boot and easy to coil one-handed. A 10m cable at ~5kg is noticeably heavier, still manageable but worth a bag. A 15m cable starts to be a two-handed job. In our own experience carrying and testing cables, the weight difference between 7m and 10m is real but not prohibitive for most people. The bulkiness (more cable to coil) matters more than the raw weight.
A carry bag is the single most impactful accessory for cable storage, independent of length. A coiled cable loose in the boot tangles, picks up dirt, and scratches itself. A cable in a padded bag stays clean, stays organised, and takes up a defined space.
The on-street charging case: when 10m+ makes sense
If you don’t have a driveway and you charge from a lamp-post or kerbside charger, the calculus changes significantly. You cannot control where you park relative to the charger. The socket may be at ankle height behind a bay marked for charging use, or on a post between two bays, or set back further from the kerb than expected.
Seven metres handles the majority of on-street public AC charging positions. But it doesn’t handle all of them, particularly for larger vehicles or rear-port cars that need to park further from the post to fit in the bay.
For regular on-street charger users, the flexibility of 10m is worth the extra weight and cost. You have one cable to carry; it needs to work in every scenario you encounter. For a full breakdown of when 10m beats 7m, see our 10m cable guide. If your situation calls for 15m or beyond, our guide to long EV charging cables (15m, 20m, 25m) covers the specialist options.
The don’t-oversize rule
Buy the cable your measurement requires, not the next size up just in case.
Every extra metre of cable you buy is extra weight, extra cost, extra voltage drop, and more to coil every time you use it. “Just in case” logic applied to cable length results in a 10m cable for someone who only ever needs 5m, a dead weight in the boot and a cost you didn’t need to incur.
The correct approach is: measure, add one metre slack, round up to the next standard length. Stop there. If your life changes (you move house, you swap your car, you start using a different charging spot), reassess then.
For everything else about which cable to choose, including connector type, power rating, and accessories, our complete cable selection guide covers the full decision.
Frequently asked questions
What length EV cable do most people need?
Seven metres suits the broadest range of UK situations. It handles single-car driveways, public AC destination chargers, and any charge port position on the car. It is the length we recommend unless your measured distance clearly requires 10m.
How do I measure what length cable I need?
Run a tape measure from your wallbox to your car’s charge port, parking in every position you use. Note the longest distance. Add one metre for drape and slack. Round up to the next standard length (5m, 7m, 10m). That is your cable.
Does a longer cable charge more slowly?
Marginally at longer lengths. At 7.4kW and 7m with a quality 6mm² cable, voltage drop is approximately 0.7%, imperceptible in practice. At 15-20m, voltage drop becomes more meaningful and conductor specification matters.
How heavy is a 7m EV charging cable?
Approximately 3-3.5kg for a 32A single-phase Type 2 cable. A 5m cable is around 2.5kg; a 10m cable around 4.5-5kg.
Can I use an extension lead to add length?
We strongly advise against it. Extension leads add connection points, resistance, and a potential overheating and fire risk at the join. They commonly void cable and vehicle warranties. If you need more reach, buy the correct length cable.
Do I need a longer cable for on-street charging?
Often yes. At a kerbside or lamp-post charger you cannot control your parking position relative to the socket. A 7m cable handles most scenarios; 10m provides the flexibility needed for larger vehicles or awkward bay layouts.
Should I buy a longer cable just in case?
No. This is the don’t-oversize rule. Longer cables are heavier, more expensive, and have slightly more voltage drop. Measure your distance, add one metre, round up. Don’t add extra beyond that.