Why does my circuit breaker keep tripping?

A breaker that trips again and again is protecting the wiring from something, and the cause is usually one of four things: an overloaded circuit, a short circuit or ground fault, a loose or damaged connection, or a breaker that has worn out. Unplugging things to test for an overload is reasonable. Finding anything else means opening walls, boxes or the panel, and that is licensed electrical work.

The four usual causes

1. An overloaded circuit. CPSC explains that a fuse or breaker opens when current goes above the safe level for that circuit, and that overloading means the appliances and lighting regularly demand more current than the home's electrical system can safely deliver.^[1] Most lighting and receptacle circuits can carry as much as 1,500 watts on a 15-amp circuit, and some kitchen circuits as much as 2,000 watts on a 20-amp circuit.^[1] A space heater, a microwave and a toaster on one kitchen circuit will pass that quickly. The giveaway is timing: it trips when the same combination of things is running.

2. A short circuit or ground fault. A short happens when current takes a path it should not, through damaged insulation, a failing appliance or water in a box. The breaker trips fast, often with a pop, and may trip as soon as you reset it. CPSC warns that a shock from an appliance can mean an internal electrical short or ground fault, and says not to touch the appliance until an electrician has checked it.^[2] Ground-fault (GFCI) breakers trip on smaller leaks to ground, so damp outdoor, bathroom and garage circuits are common culprits.

3. A loose or damaged connection. Wires that have worked loose at an outlet, switch, light fixture or the breaker itself heat up and can arc. CPSC says a loose connection, such as a plug that slips in and out of an outlet, is likely to overheat, and lists arcs, sparks, sizzles, buzzes and the odor of hot insulation among the warning signs of a potential hazard.^[1] An arc-fault (AFCI) breaker is built to trip on this kind of arcing, so a nuisance-looking AFCI trip can be a real warning.

4. A worn or faulty breaker. Breakers age, and one that has been tripping for years can become weak, trip below its rating or fail to hold in place. This is the least likely cause and the one to rule out last, because a breaker that trips is far more often reacting to a real problem than causing one.

What you can check without opening anything

Everything below happens at the breaker handles, with dry hands and no water nearby. CPSC says to check which breaker tripped and which appliances lost power, add up the wattage on their rating labels, and, if the total exceeds what the circuit allows, move an appliance to another circuit with fewer appliances; if that is not possible, it says to get help from a qualified electrician.^[1]

Pay attention to patterns, because they are what an electrician will ask about:

• Does it trip only when one appliance runs, or when several run together?
• Does it happen at certain times, such as when it rains, when the heat or air conditioning starts, or in the evening?
• Does it trip with everything unplugged?
• Which outlets, lights and rooms go dead when it trips?

For repeated outages CPSC suggests keeping track of which circuits are affected and which appliances are in use when the power goes out, then consulting a qualified electrician.^[1] A short note on your phone is enough. Our guide to resetting a tripped breaker safely covers what to do at the panel after a single trip.

GFCI and AFCI breakers

If the tripping breaker has a test button, it is a GFCI or AFCI type. CPSC says GFCIs protect against electrocution, AFCI breakers detect arcing from a damaged wire or connection, and both can stop working without showing any sign of failure.^[2] CPSC recommends testing GFCI and AFCI breakers monthly, and says a defective one should be replaced by a qualified electrician.^[2] If one will not stay reset after you unplug everything on the circuit, stop and call.

What not to do

Do not tape a breaker on, hold it in place, or swap in a higher-rated one to stop the nuisance. CPSC warns that panels with overrated fuses or breakers on 15- or 20-ampere lighting and receptacle circuits allow overloading that can lead to fire, and that when protection keeps tripping you should keep track of which circuits are affected and consult a qualified electrician.^[1] The breaker is sized to protect the wire in the wall, and a bigger one lets the wire overheat first. Do not remove the panel cover either; that is the electrician's job.

When to call a licensed pro

Call one if a breaker trips more than once for no clear reason, trips with nothing plugged in, will not reset, or comes with a burning smell, buzzing, sparks, heat or moisture. Turn off the main breaker if you see sparks or smell burning, and treat it as urgent.

Finding the fault means testing the circuit, tightening or replacing connections, and sometimes replacing a breaker or wiring. Under Virginia law, no individual may do or offer tradesman work, which includes the electrical trade, for compensation without a licence, with an exception for people working under a licensed tradesman's supervision.^[3][4] Check the licence on the Board for Contractors' lookup before anyone opens your panel. The Board warns that a licence number printed on an advertisement or business card does not necessarily mean the licence is valid.^[5]

For the visit itself, read when to call an electrician about a breaker panel and what a breaker replacement costs in Virginia. More guides are in the electrical answers hub, and you can browse local electricians.

If a breaker keeps tripping, describe the problem once and licensed local electricians quote it.