A granny charger (also called a Mode 2 portable EV charger) is the cable that plugs into a standard 3-pin UK socket and charges your car at about 2.3kW (10A). It's slow, it's not meant for daily use, and it's the most-misunderstood product in EV charging. Used correctly, it's a brilliant backup. Used incorrectly, it's a fire risk.
What a granny charger is for
A granny charger is for occasional or emergency charging. Use cases where it's perfect:
- You've moved and the wallbox isn't installed yet: a granny charger keeps your EV on the road for the 1-2 weeks until install.
- Holiday let or second home: adds 80-100 miles overnight from a standard outlet, no install needed.
- Visiting friends or family: they have a 3-pin outdoor socket; you don't drain their hospitality with public-charger detours.
- Backup if your wallbox fails: keeps you mobile while the warranty claim runs.
Use cases where it's the wrong tool: every-night charging on a daily commute. UK 13A plugs and ring-final circuits are not designed for 6-8 hour continuous full-load draws. Use a wallbox at home if you charge daily.
Power and charging speed
Most granny chargers run at 2.3kW (10A): about 8 miles of range per hour, or 80-90 miles overnight on a 10-hour charge. A few units (the Wottz Type 2 portable, for example) can be switched between 6A, 8A, 10A and 13A modes. The 13A setting only works on a dedicated outdoor 13A socket on its own circuit; using it on a shared kitchen ring is a fire hazard. Stick to 10A on standard household sockets.
Connector type
Your granny charger needs to match your car's charge port. Type 2 covers every UK EV sold new since 2018. Type 1 is for older Nissan Leaf (24/30 kWh), Mitsubishi Outlander PHEV (Mk1), first-gen BMW i3 and a handful of Japanese-import EVs. We stock both: see Type 2 and Type 1 ranges.
Safety: what to look for
A granny charger draws sustained high current for hours. The cheap "bargain" units on Amazon and eBay are the most common cause of UK EV charging fires. Every cable we sell is rated to:
- IEC 62752: the international standard for in-cable control and protection devices.
- IP55 minimum: weatherproof to UK rain.
- Built-in temperature sensor: auto-throttles or cuts out if the socket overheats.
- Built-in DC leakage protection: Type B equivalent; doesn't trip the household RCD.
- 2-year minimum warranty: administered by us, not the manufacturer.
The 18th Edition rule for daily use
UK wiring regulations (BS 7671:2018+A2:2022) explicitly recommend that EV charging is done from a dedicated circuit with Type B RCD protection, not a shared household ring final. If you find yourself relying on a granny charger more than once or twice a week, the right next step is either a dedicated outdoor 13A or 16A socket on its own circuit (cheap, electrician-installed in a couple of hours) or a proper home wallbox. A granny charger is the bridge, not the destination.
Cable length
5m is the standard length and works for almost every "near the back door" charging scenario. 10m gives you reach across a driveway. 15-20m is for awkward layouts where the only available socket is far from where the car parks, but bear in mind that longer cables are heavier to coil and slightly more expensive. See our extension lead range if you need to reach further than the cable itself allows.