You can replace a breaker yourself, but only if the main panel is not actively sparking or smoking

A circuit breaker is a switch inside your electrical panel that cuts power to a circuit when it detects a problem—usually an overload or a short. When a breaker trips repeatedly, won't reset, or is visibly damaged, it needs to be replaced. You can do this work yourself if you follow the safety steps exactly, but if you see arcing (bright sparks), smell burning plastic, or feel heat radiating from the panel, stop and call a licensed electrician. Do not attempt this repair if you are not comfortable working inside an electrical panel.

The job takes 15 to 30 minutes once you have the right breaker. The hardest part is identifying which breaker you need—they come in different amperages (15, 20, 30, 50 amp, and others) and must match the circuit they protect. Buying the wrong one creates a fire risk.

Key Takeaways

  • Turn off the main breaker before opening the panel, then verify power is off using a non-contact voltage tester on the bus bars inside.
  • Identify the failed breaker by its position and amperage rating, then buy an exact replacement from the same manufacturer as your panel.
  • Remove the old breaker by turning its handle to off, unbolting the wire, sliding it out, and inserting the new one in the same slot.
  • If the breaker trips again immediately after replacement, the circuit has a short or overload that a licensed electrician should diagnose.
  • Some panel types and older homes require a licensed electrician by law; check your local electrical code before starting.

Gather the right tools and safety equipment

You need a non-contact voltage tester (also called a voltage detector)—this is the single most important tool. It costs $10 to $20 and tells you whether power is actually off before you touch anything inside the panel. Do not skip this step. You also need a flathead screwdriver to unbolt the wire from the breaker, a flashlight or headlamp, and the replacement breaker itself.

Wear safety glasses and work gloves. Keep one hand in your pocket or behind your back while working inside the panel—this reduces the risk of current flowing across your chest if you accidentally touch a live part. Have someone else in the house with you, or at least tell someone where you are and what you are doing.

Turn off power and verify the panel is safe

Locate your main breaker at the top or bottom of the panel (it is usually larger than the others and labeled "Main"). Switch it to the off position. The panel is now de-energized, but the main lugs—the thick copper terminals where power enters—are still live. Do not touch them.

Use your non-contact voltage tester to confirm power is off. Touch the tester to the bus bars (the metal rails where breakers connect) and to the wires inside the panel. The tester should show no voltage. If it beeps or lights up, power is still on—do not proceed. Call an electrician or contact your utility company if the main breaker does not cut power.

Identify and locate the failed breaker

Open the panel door and look at the breaker you need to replace. Write down its position (top left, middle right, etc.), its amperage rating (printed on the handle), and the brand name of the panel (usually stamped on the inside of the door). This information tells you exactly what to buy.

Breakers are not interchangeable between panel brands. A breaker made for a Siemens panel will not fit safely in a General Electric panel, even if it looks similar. Go to a hardware store or electrical supply house with this information and buy an exact match. If you cannot find the same brand, a licensed electrician can advise you on compatible options for your specific panel.

Remove the old breaker and install the new one

Flip the handle of the failed breaker all the way to the off position. Locate the wire connected to the breaker terminal (the screw on the side or back of the breaker). Use your flathead screwdriver to loosen this screw and remove the wire. Set the wire aside—do not let it touch anything metal.

Most breakers slide into a slot on the bus bar. Push the breaker handle down and toward the center of the panel to disengage it, then slide it straight out. Insert the new breaker into the same slot, pushing it firmly until it clicks into place. The handle should be in the off position. Reconnect the wire to the terminal screw and tighten it firmly—a loose connection creates heat and fire risk.

Flip the new breaker handle to the on position. The panel should not spark or make noise. If it does, flip it back off immediately and call an electrician.

Test the circuit and watch for problems

Close the panel door and turn the main breaker back on. Go to the circuit the new breaker protects and plug in a lamp or device to test it. Power should flow normally. If the new breaker trips immediately when you turn it on or when you plug something in, the circuit has a short or an overload. Do not keep resetting it—this creates a fire hazard. Call a licensed electrician to find and fix the underlying problem.

If the breaker holds and the circuit works, you are done. Monitor the breaker over the next few days. If it trips again under normal use, there is still a problem on that circuit that needs professional diagnosis.

When to call a licensed electrician instead

Some states and municipalities require a licensed electrician to replace breakers, even in your own home. Check your local electrical code or call your building department before you start. Some panel types—particularly older Federal Pacific Electric (FPE) or Zinsco panels—have known safety issues and should only be serviced by a professional. If your panel is one of these, hire an electrician.

Also hire an electrician if the breaker you need is not a standard single-pole breaker (15, 20, or 30 amp), if the panel is wet or corroded, if you see any burn marks or melted plastic inside, or if you are not confident working inside an electrical panel. The cost of a service call is far less than the cost of an electrical fire.

Frequently Asked Questions

Can I replace a breaker while the main breaker is on?

No. The main breaker must be off before you open the panel or touch any breaker. Even with the main off, the main lugs remain live, so use a voltage tester to confirm the bus bars are de-energized before you work.

What if the new breaker trips immediately?

This means the circuit has a short circuit or is overloaded. Do not keep resetting it. Turn the breaker off and call a licensed electrician to find the problem. Repeatedly tripping a breaker creates a fire risk.

Do I need to turn off the whole house to replace one breaker?

Yes, you must turn off the main breaker. This de-energizes the panel so you can work safely. You do not need to turn off individual breakers—the main breaker controls everything.

What if I buy the wrong breaker?

Return it and buy the correct one. Installing a breaker that does not match your panel brand or amperage rating creates a serious fire hazard. Take the time to get the exact replacement.

How do I know if my panel brand is one that requires a professional?

Federal Pacific Electric (FPE) and Zinsco panels have documented safety problems and should be serviced only by a licensed electrician. If your panel is older or you are unsure of the brand, call an electrician for an inspection before attempting any work yourself.