Power cut or tripping switches? What to check before calling an electrician

Losing power suddenly is unsettling, but before assuming the worst or calling an electrician out at an emergency call-out rate, it is worth spending a couple of minutes working out what is actually going on, since the cause, and the right next step, can be quite different depending on the answer.

The first useful check is simply whether the problem is limited to your home or affects the wider area. Look outside: if streetlights, neighbouring houses, or nearby shops also appear to have lost power, you are very likely dealing with a genuine power cut on the wider electricity network rather than a fault inside your own home, and no amount of checking your own consumer unit will fix that. If your neighbours clearly still have power and it is only your property affected, the cause is much more likely to be something inside your home — most commonly a tripped switch at your own consumer unit.

If it looks like an issue inside your own property, go to your consumer unit and check the position of the main switch, which is usually the largest switch on the board and is often coloured red. If it has moved to the "off" position, the safest first step is to make sure anything plugged in is switched off, or unplugged, before flipping the main switch back to "on" — this avoids the possibility of an already-faulty appliance immediately tripping the switch again as soon as power is restored. If individual circuit breakers or RCDs (rather than just the main switch) have tripped, the same principle applies: turn off or unplug what is on that circuit before resetting it, then reintroduce appliances one at a time if you are trying to identify which one caused the trip.

It is important not to keep repeatedly resetting a switch that trips again immediately. If a circuit trips again as soon as you reset it, with nothing plugged in, or trips again quickly after you plug something back in, this points to a genuine fault — either in the fixed wiring or in a specific appliance — rather than something you should keep working around by resetting it. Repeated resetting does not fix an underlying fault and can, in some circumstances, make an existing problem worse. This is the point at which it is sensible to stop and call a registered electrician rather than continuing to try to solve it yourself.

If the problem does turn out to be a wider power cut rather than something inside your home, the number to know is 105 — a free service, available from any phone, that connects you directly to your local electricity Distribution Network Operator (DNO), the company responsible for the power lines and infrastructure in your specific area. You can also call 0800 6783 105 as an alternative, and Text Relay users can dial 18001 before either number. Calling 105 gets you the most accurate, up-to-date information on a power cut in your specific area, including likely restoration times where these are known, and is the right first call rather than assuming it is a fault only an electrician can fix.

A short list of safe basics is worth keeping in mind regardless of the cause: never touch a consumer unit or any exposed wiring with wet hands or while standing on a wet floor; if you are relying on candles during a power cut, keep them well away from anything flammable and never near a gas appliance; avoid overloading extension leads or adaptors, particularly if you are running additional appliances during an outage; and if food in a fridge or freezer is affected by a prolonged cut, most guidance suggests food generally stays safely cold for several hours in a closed fridge and considerably longer in a full, closed freezer, though it is worth checking specific guidance if an outage runs long.

Certain signs genuinely do point to an emergency rather than a routine trip, and are worth treating seriously: a burning smell, visible sparks, scorch marks or discolouration around a socket or the consumer unit, exposed or damaged wiring, or a switch that will not reset even once everything is unplugged. In any of these situations, it is sensible to isolate the affected circuit if you can safely do so, avoid using the affected socket or area, and call an electrician promptly; if there is any visible fire risk, treat it as a fire emergency and call 999 rather than waiting for an electrician.

This article is general safety information, not a substitute for professional advice, and if you are ever unsure or uncomfortable checking a consumer unit yourself, it is always reasonable to call a qualified electrician rather than investigating further on your own. Our directory lists UK electricians by area if you need one.

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