How to Shut Off Power at Your Electrical Panel

Why this matters

Sometimes the right move is to take power away: an outlet that sparked, a ceiling light with water dripping out of it, an appliance that smells hot and will not switch off, or an electrician on the phone asking you to turn off a circuit before they arrive. Knowing how to do that at the panel, and knowing when not to go near the panel at all, turns a few anxious minutes into a calm one. This card covers turning off one circuit, turning off the whole house, and bringing power back without creating a new problem.

Before anything else: if there is water on the floor in front of the panel, water on or coming out of the panel, sparking, smoke, a burning smell or buzzing from the panel itself, do not approach it. Leave the area. Call 911 if there is smoke or fire, and call your electric utility, which can disconnect power at the meter from outside.

The panel, and what you are looking for

The panel (also called the breaker box) is a gray metal box, usually in a garage, basement, utility room or hallway closet. Opening its door is fine. Behind the door is a flat metal cover, called the dead front, with the breaker handles poking through it. That cover stays on. Everything you need is on the outside of it, and even with the main off, the heavy wires coming in from the meter are still live behind it.

 DOOR OPEN, FLAT COVER (DEAD FRONT) STAYS ON
+--------------------------------------------+
|         +--------------------+             |
|         |     MAIN   200     |  main       |
|         +--------------------+  breaker:   |
|                                 whole house|
|   1 [15]--|   |--[20] 2                    |
|   3 [15]--|   |--[20] 4                    |
|   5 [30]--|   |--[40] 6   5+7 and 6+8 are  |
|   7 [30]--|   |--[40] 8   tied 240 V pairs |
|   9 [20]--|   |--[15] 10                   |
|  11 [20]--|   |--[15] 12  singles: 120 V   |
+--------------------------------------------+
  number in brackets = amps printed on handle
  ON = handle toward center, OFF = toward edge
  directory chart is on the inside of the door

Main breaker. The big handle, usually at the top, marked with a number such as 100, 150 or 200: the amps the whole house can draw. Turning it off turns off everything that panel feeds.

Branch breakers. The rows of smaller handles, each feeding one circuit. A single handle feeds 120-volt outlets and lights. Two handles tied together feed a 240-volt appliance such as a dryer, range, electric water heater or air conditioner.

Directory. The chart on the inside of the door that says which breaker feeds what. If yours is blank, or says "bedroom" for six different breakers, fix it on a calm day. See related: How to Label Your Electrical Panel Directory.

What changes the picture:

• No main handle in the panel. Some houses have the main disconnect in a separate box outside beside the meter. Houses built under the 2020 or later edition of the National Electrical Code also have an outdoor emergency disconnect near the meter (NEC 230.85, as adopted by your jurisdiction), so firefighters can cut power without going inside. If your indoor panel has no big handle, look outside.
• Several handles that together are the main. Some older panels have no single main. Instead, a group of up to six handles is labeled as the service disconnects, and every one of them has to be off to shut off the house. If yours is like that, write it on the door.
• A second panel. A subpanel in a garage, basement or addition is fed from a breaker in the main panel. The main turns the subpanel off too; the subpanel's own breakers turn off only what it feeds.

Step 1: Check the floor and your hands before you reach

Both must be dry. Wear shoes, and stand on a dry surface. If a basement floor is damp but not flooded, a dry rubber mat or board to stand on is better than bare wet concrete.

Why: your body becomes the path electricity takes when something inside the panel is not right, and water makes that path easy. With dry hands and dry footing, flipping a breaker on a healthy panel is an ordinary household task.

What breaks if you skip it: the day a panel has a problem is often the day water is involved. If the water is more than a damp film, or you cannot tell where it is coming from, stop here and call the utility.

Step 2: Stand to the side and touch the handle only

Stand beside the panel, not squarely in front of it, reach across with one hand, and turn your face away as you move the handle. Touch nothing but the handle: not the cover screws, not a wire, not the inside of the box. Keep your other hand off the metal box and off any pipe nearby.

Why: a breaker almost never fails when you switch it, but if a damaged one ever does, the flash and heat come out the front. Standing to the side keeps your face out of that path.

What breaks if you skip it: nothing, most days. The step exists for the rare breaker that is damaged inside, and you cannot see that from outside.

Step 3: Turn off one circuit, then prove it is off

Find the breaker on the directory and push its handle firmly all the way to OFF, toward the outer edge on most panels. You should feel it snap over.

Then prove it. Take a lamp, plug it into an outlet on another part of the house and confirm it lights. Then plug it into the outlet you are worried about, or flip the wall switch for the light. If it stays dark, carry it back to the first outlet and confirm it still lights there.

Why: directories are often wrong, and one outlet can be on a different circuit from the one beside it. A dark lamp only means "off" if you saw that same lamp light just before and just after.

What breaks if you skip it: you believe the sparking outlet is dead and it is not. If the lamp still lights, turn that breaker back on so you do not lose track of what you changed, and try the next likely one, or go to Step 4.

Step 4: Turn off the whole house when you cannot find the circuit

If the directory is no help, or the problem touches more than one circuit (water coming through a ceiling with lights in it, for example), turn off the main. Same rules: dry, to the side, handle only, face away, firmly to OFF.

Think for ten seconds about what goes off with it:

• Sump pump. It stops pumping. If water is rising in the basement, say so when you call for help.
• Medical equipment, such as an oxygen concentrator. Have its backup ready first.
• Well pump, if you have one. No water at the taps while the power is off.
• Refrigerator and freezer. Keep the doors shut; they stay cold far longer closed.
• Garage door opener. Use the manual release cord if you need to get a car out.

Why: the main is one certain answer when there is no time to guess, and it also catches anything you did not know shared a circuit.

Step 5: Mark it and leave it off

It stays off until whatever made you turn it off has been dealt with. Tell everyone in the house, and put a strip of painter's tape across the handle reading "OFF - do not turn on" with the time, so nobody helpfully flips it back.

Write down which breaker, the time and why. An electrician arriving later works faster from that note, and it belongs in your records afterwards. See related: Your House Records File and What Goes In It.

Step 6: Bring the power back, with a check first

This is the step people rush.

• The reason is gone. The water has stopped and the area is dry, the appliance is unplugged, or the electrician has said it is ready. If water got into an outlet, a light fixture or the panel, power stays off until an electrician has looked. Do not turn it back on to "dry things out."
• Big loads off first. Set the furnace or air conditioner to off at the thermostat and unplug space heaters, so everything does not start at the same instant.
• Same stance as before. Dry hands, stand to the side, handle only, face away.
• Main first, then branches. If a branch breaker trips again the moment it goes on, leave it off. See related: How to Reset a Tripped Breaker Once.
• Stay and watch for a minute. Stand near the area that had the problem. Sparking, crackling, a burning smell or flickering means the breaker goes back off and you call an electrician.

Worked example: one sparking outlet, then a dripping ceiling

The house: two stories, a 200-amp panel in the attached garage, main breaker at the top, a directory listing 24 circuits. Position 7 reads "Kitchen counter right" and position 9 reads "Kitchen counter left."

A Tuesday morning, 7:40. Plugging a toaster into the outlet right of the sink, the homeowner sees a bright spark at the plug and hears a pop. Nothing is burning, but the outlet face has a dark mark. She pulls the toaster out by the plug body, not the cord. The garage floor is dry. She stands to the left of the panel, faces away, and pushes breaker 7 to OFF.

She plugs a bedside lamp into a living room outlet, where it lights, then into the marked kitchen outlet. It lights there too, so breaker 7 is not this outlet. She turns 7 back on, turns 9 off and tries again. This time the lamp stays dark in the kitchen outlet, and it lights again when she carries it back to the living room, so the lamp works and breaker 9 is the one. She tapes 9, writes "9, kitchen right of sink, spark 7:40 a.m." on the tape and in her notes, corrects the directory in pencil, and calls an electrician. The rest of the kitchen stays on for the day.

What would have changed it: if the outlet had kept smoking after the toaster came out, or the burning smell had been coming from the panel, she would not have gone to the garage at all. She would have left the house, called 911 for the smoke, and let the utility cut power at the meter.

Two weeks later. An upstairs toilet supply line fails while the house is empty for an afternoon, and water is coming through the kitchen ceiling around a recessed light when she gets home. She closes the main water valve first (see related: How to Close Your Main Water Valve and Fixture Stops), then checks the garage: dry floor, no water anywhere near the panel. The directory does not say which breaker feeds the kitchen ceiling lights, and water is running across a light fixture, so she does not guess. She turns off the main, leaving the garage chest freezer's lid shut. The power stays off until the electrician checks the fixture the next morning, and she turns the main back on only after he says so, with the air conditioner set to off at the thermostat first. The main water valve stays closed until the failed supply line has been replaced; then she opens it slowly and checks under that toilet for drips.

What would have changed that: if the water had been running down the garage wall toward the panel, she would have stayed out of the garage and called the utility from outside.

When you stop and call someone

• Electrician: a breaker that will not stay on, a scorched or melted outlet, any water inside a fixture or outlet, or a panel that is warm to the touch, buzzes, or shows rust or scorch marks on the cover.
• Electric utility: when you cannot safely reach the panel, or the main will not turn off. Do not pull the meter or open the meter base yourself. The wires feeding it stay live no matter what you switch inside the house.
• 911: smoke, fire, sparking that does not stop, or anyone who has been shocked.

See related: When to Stop and Call a Licensed Pro Around the House.

References

• NFPA 70, National Electrical Code, Section 230.85 (outdoor emergency disconnect for one- and two-family dwellings, added in the 2020 edition), as adopted by your jurisdiction
• See related: Your Home's Shutoffs: Water, Gas and Electric
• See related: Reading Your Electrical Panel and Its Breakers
• See related: How to Reset a Tripped Breaker Once
• See related: When to Stop and Call a Licensed Pro Around the House