Electricity saving box: what it is and does it work?

What is an electricity saving box?

It's a plug-in unit, usually with a capacitor inside, designed to improve how power is used on the circuit it's connected to. Industrial versions are large cabinets; home versions plug into a socket.

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Do electricity saving boxes work?

Results depend on your home's appliances, circuits and tariff, and cheap boxes vary wildly in quality. The fair test is your own smart meter: note readings before and after over similar weeks.

WattLock comes with a 30-day money-back guarantee so you can run that test without risk.

How to choose a safe one

• Built to the UK plug standard
• Fire-resistant casing and approved components
• A real UK seller with a returns policy
• Avoid £10 unbranded boxes from marketplaces

Electricity saving box vs WattLock

WattLock is a type of electricity saving box – a plug-in unit that connects to the circuit through an ordinary socket. The difference between a good one and a poor one comes down to build quality, plug design, honest information and the seller standing behind it.

• UK 3-pin plug, not a European plug with an adaptor
• Fire-resistant casing rather than thin, cheap plastic
• Approved capacitor-based TrueWatt circuit inside
• 30-day money-back guarantee and UK email support

What the critics say – and our view

Consumer groups have warned about cheap boxes that make big claims. We agree that no plug-in device should promise to halve your bill, and some products have been unsafe. That's why we give clear safety information, avoid fixed-percentage promises and let you test WattLock with a full refund if it's not for you.

Getting the best from an electricity saving box

• Fit one per socket circuit – not one per house
• Plug directly into the wall
• Combine it with simple habits: LED bulbs, washing at 30°C, switching off standby
• Track results with your smart meter over several weeks