How to Replace a Tripped or Failed Circuit Breaker

You can replace a circuit breaker yourself, but the panel stays live

A circuit breaker can be replaced at home without calling an electrician, but the main electrical panel remains energized even when you turn off the main breaker. This means live electricity is present inside the panel at all times. If you are not confident working inside an electrical panel, or if your panel is wet, corroded, or damaged, hire a licensed electrician instead. The job takes 15 to 30 minutes once you have the right breaker model and tools.

Before you start, you need to know which breaker failed and what amperage it handles. Look at the breaker itself — the amperage is printed on the switch (usually 15, 20, 30, 50, or 100 amps). You also need to identify your panel brand: Square D, Siemens, GE, Eaton, and Cutler-Hammer are the most common. Different brands use different breaker designs, and putting the wrong breaker in the wrong panel can cause a fire.

Key Takeaways

The main electrical panel stays live even when the main breaker is off, so treat all work inside the panel as dangerous and work carefully.
You must buy a replacement breaker that matches your panel brand and amperage rating exactly — Square D breakers do not fit Siemens panels.
Turn off the breaker you are replacing and test the circuit with a non-contact voltage tester to confirm power is off before touching anything inside the panel.
The breaker clips into a metal rail inside the panel and connects to a neutral bus bar with a wire; removing and installing it takes only a few minutes once the panel cover is off.
If the breaker trips repeatedly after replacement, the circuit has a short or overload — do not keep resetting it, because that is a fire hazard.

Gather the right breaker and tools before opening the panel

Go to a home improvement store or electrical supply shop with a photo of your panel or the panel door itself. Tell the staff your panel brand and the amperage of the breaker you need. They will hand you the correct replacement. Do not guess or buy a generic breaker — it will not fit or work safely.

You will also need a non-contact voltage tester (about $10 to $20), a flashlight or headlamp, and a flathead screwdriver. The voltage tester is the most important tool: it beeps or lights up when it detects live electricity, and it lets you confirm that power is actually off before you touch anything inside the panel. Do not skip this step.

Turn off the breaker and test for power

Locate the breaker that is tripped or failed. A tripped breaker usually sits in the middle position between ON and OFF, or it may be all the way OFF. Flip it to the OFF position if it is not already there. Wait a few seconds.

Now use your non-contact voltage tester on the breaker you are about to remove. Hold the tester near the breaker switch and the wire connected to it. If the tester beeps or lights up, power is still on — do not proceed. If it stays silent and dark, power is off. Test it again on a breaker you know is live (like one powering a light that is on) to make sure the tester works. Then test your target breaker one more time.

Remove the panel cover and locate the breaker

Use a flathead screwdriver to remove the two or four screws holding the panel cover in place. Set the cover aside in a safe spot where it will not get lost. You will now see the inside of the panel: a metal box with breakers arranged in two columns, a neutral bus bar (a metal strip with many wires attached), and a ground bus bar.

Find the breaker you need to replace. It will be a switch about the size of your thumb, clipped onto a metal rail that runs vertically down the center of the panel. The breaker has one wire connected to it (the hot wire) and sits next to the neutral bus bar. Use your flashlight to see clearly.

Disconnect the wire and remove the old breaker

Before you touch the breaker, test it one more time with your voltage tester. The tester should show no power. Once you are certain, use your screwdriver to loosen the screw on the breaker terminal — the small metal post where the wire connects. Turn the screw counterclockwise until the wire is loose enough to pull out by hand. Set the wire aside.

Now grip the breaker firmly and pull it straight out of the panel. It clips onto the metal rail, so it will take some force — pull steadily and do not twist. The breaker will come free. Set it aside; you will not need it again.

Install the new breaker and reconnect the wire

Take your new breaker and align it with the metal rail where the old one was. The breaker has a clip on the back that hooks onto the rail. Push the breaker straight in until you hear or feel it click into place. It should sit flush with the other breakers, not sticking out.

Now take the wire you disconnected and insert it into the terminal on the new breaker. Use your screwdriver to tighten the terminal screw clockwise until the wire is snug. Do not over-tighten — you want the wire held firmly, not crushed. Tug the wire gently to confirm it is find.

Close the panel and test the circuit

Replace the panel cover and screw it back in place. Use your screwdriver to tighten all screws evenly — do not over-tighten or you may crack the cover.

Now flip the new breaker to the ON position. If the circuit powers up and stays on, the job is done. If the breaker trips when ready or within a few minutes, turn it off and leave it off. A breaker that trips repeatedly means the circuit has a short circuit or is overloaded. Do not keep flipping it back on — that creates a fire hazard. Call a licensed electrician to find and fix the problem.

Frequently Asked Questions

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

Yes, the main breaker being on does not make the job more dangerous — the panel is live either way. However, turning off the main breaker does cut power to most of the panel, which can make the work feel safer and lets you work faster. The safest approach is to turn off the main breaker, then turn off the individual breaker you are replacing, then test with a voltage tester before touching anything.

What if the breaker is stuck and will not pull out?

Do not force it — a stuck breaker usually means it is clipped in tightly or the panel is old and corroded. Wiggle it gently side to side while pulling straight out. If it still will not budge, stop and call an electrician. Forcing it can damage the breaker, the rail, or the panel itself.

How do I know if I have the right breaker model?

The breaker must match your panel brand exactly. Look at the panel door or inside the panel for the manufacturer name — it is usually printed clearly. Then match the amperage printed on the old breaker. If you are unsure, take a photo of your panel to an electrical supply store and ask the staff to confirm the model before you buy.

What should I do if the new breaker trips right after I install it?

Turn it off when ready and leave it off. A breaker that trips right away means the circuit has a short or is drawing too much power. Flipping it back on repeatedly is a fire hazard. The circuit needs to be inspected by a licensed electrician to find the problem before the breaker is used again.

Do I need a permit to replace a breaker myself?

Permit requirements vary by city and county. Some places require a permit and inspection for any work inside an electrical panel, while others allow homeowners to do it without one. Check with your local building department before you start. If a permit is required and you skip it, you may have trouble selling your house later or getting insurance to cover damage from electrical problems.

This guide is for general information only and is not medical, financial, legal, or other professional advice. For decisions specific to your situation, consult a qualified professional. See our Editorial Policy.