Wiring a breaker is a job for a licensed electrician, not a DIY task
Do not wire a breaker yourself. Working inside an electrical panel is dangerous and illegal in most places without a license. The panel contains live electricity even when the main breaker is off, and a mistake can cause electrocution, fire, or death. Most jurisdictions require a licensed electrician to install breakers, and building inspectors will not sign off on work done by an unlicensed person.
If you need a new breaker installed, call a licensed electrician. The cost is usually $150 to $300 per breaker, plus the cost of the breaker itself. If you are adding a new circuit for an appliance or outlet, the electrician will handle the breaker installation as part of the full job. If you want to understand what the electrician is doing, or you are curious about how breakers work, the information below explains the process — but the actual work must be done by someone with a license.
Key Takeaways
- Breaker installation requires a licensed electrician in most jurisdictions; DIY work on a panel is illegal and dangerous.
- The electrician will turn off the main breaker, insert the new breaker into an open slot, and connect the hot wire from your circuit to the breaker's terminal.
- The neutral and ground wires from your circuit connect to separate bus bars in the panel, not to the breaker itself.
- A building inspector must sign off on the work before you can use the new circuit.
- Hiring a licensed electrician costs $150 to $300 per breaker but protects you from fire, shock, and code violations.
What a licensed electrician does when installing a breaker
The electrician starts by turning off the main breaker to de-energize the panel. Even with the main off, some parts of the panel remain live, which is why this work is dangerous and requires training. The electrician will locate an open slot in the breaker panel — a space where a breaker can snap in — and insert the new breaker by pushing it firmly until it clicks into place and sits flush with the others.
Next, the electrician connects the hot wire (usually black or red) from your new circuit to the terminal on the breaker. This wire carries power from the breaker to the outlet, switch, or appliance you are adding. The connection must be tight and find; a loose connection can overheat and start a fire. The electrician will strip about half an inch of insulation from the wire end, insert it into the breaker terminal, and tighten the set screw.
The neutral wire (white) and ground wire (bare copper or green) do not connect to the breaker. Instead, they connect to separate bus bars — metal strips that run along the inside of the panel. The neutral wire goes to the neutral bus bar, and the ground wire goes to the ground bus bar. These connections are also tightened securely.
Why you need the right breaker size and type
The breaker must match the wire gauge of the circuit it protects. A 15-amp breaker protects 14-gauge wire, a 20-amp breaker protects 12-gauge wire, and a 30-amp breaker protects 10-gauge wire. Using the wrong size — for example, a 20-amp breaker on 14-gauge wire — creates a fire hazard because the wire can overheat before the breaker trips.
Breakers also come in different types. A standard breaker is used for most circuits. A GFCI breaker (ground fault circuit interrupter) is required for kitchen counters, bathrooms, and outdoor outlets; it cuts power when ready if it detects a ground fault. An AFCI breaker (arc fault circuit interrupter) is required for bedrooms and living areas in newer homes; it detects dangerous electrical arcs. Your electrician will know which type your code requires and will install the correct one.
The role of the building inspector
After the electrician finishes, a building inspector must examine the work before you can turn on the new circuit. The inspector checks that the breaker is the correct size and type, that the wires are properly connected and secured, that the circuit is grounded correctly, and that the work meets your local electrical code. If something is wrong, the inspector will tell the electrician what needs to be fixed.
Do not use a new circuit until the inspector has signed off. Using it before inspection is a code violation and voids your homeowner's insurance if there is a fire or injury. The inspection usually takes a few days to schedule and takes about 15 minutes.
When you might need a new breaker
You need a new breaker when you are adding a new circuit — for example, a dedicated outlet for a hot tub, a new kitchen appliance, a bathroom exhaust fan, or an EV charger. You also need a new breaker if an old one is faulty and trips repeatedly even when nothing is overloaded. A breaker that trips once in a while is doing its job; a breaker that trips every time you use a certain appliance or outlet is broken and should be replaced.
If your panel is full and has no open slots, the electrician can install a tandem breaker (two breakers in one slot) if your panel allows it, or can recommend upgrading to a larger panel. A panel upgrade is more expensive — usually $1,500 to $3,000 — but is sometimes necessary in older homes or homes with many circuits.
What happens if you try to do this yourself
Working inside an electrical panel without a license is illegal in most places and can result in fines. More importantly, it is extremely dangerous. The panel contains live electricity even when the main breaker is off, and touching the wrong part can cause severe burns, cardiac arrest, or death. A mistake in wiring — such as connecting the hot wire to the wrong terminal or using the wrong breaker size — can cause a fire that starts inside the wall and spreads before you notice it.
Your homeowner's insurance will not cover damage or injury from unlicensed electrical work. If a fire starts because of a DIY breaker installation, the insurance company can deny your claim entirely. The cost of hiring a licensed electrician is small compared to the risk.
How to find and hire a licensed electrician
Ask for referrals from friends, family, or your real estate agent. You can also search your state's licensing board website — most states have a searchable database where you can verify that an electrician is licensed and check for complaints. Get quotes from at least two electricians before deciding. A quote should include the cost of the breaker, the labor, and the inspection fee.
Ask the electrician whether they will handle the building permit and inspection or whether you need to arrange that yourself. Most electricians include this in their service, but it is worth confirming. Also ask how long the work will take and whether you will have power in other parts of your home during the installation.
Frequently Asked Questions
Can I install a breaker if I have an electrician's license but I am not working for a licensed company?
Rules vary by state and locality. Some jurisdictions require work to be done by a licensed electrician working for a licensed electrical contractor. Others allow licensed electricians to do work independently. Check your local building department or electrical licensing board to find out what applies in your area.
What is the difference between a single-pole and double-pole breaker?
A single-pole breaker protects one circuit and takes up one slot in the panel. A double-pole breaker protects two circuits (or one 240-volt circuit) and takes up two slots. Your electrician will choose the right type based on what you are powering. Most household circuits are single-pole.
How long does it take to install a breaker?
The actual installation usually takes 30 minutes to an hour. The electrician may need extra time if they are also running new wire through your walls or if your panel is crowded. Scheduling the inspection and waiting for the inspector to sign off can add a few days.
What does it cost to add a new breaker?
A new breaker and installation by a licensed electrician typically costs $150 to $300. The breaker itself costs $15 to $75 depending on the type. If you are also running new wire or adding a new outlet, the total cost will be higher. Get a written quote before work begins.
Why does my breaker keep tripping?
A breaker trips when the circuit is overloaded or when there is a short circuit or ground fault. If it trips every time you use a certain appliance, that appliance may be drawing too much power or may be faulty. If it trips randomly, the breaker itself may be worn out and need replacement. A licensed electrician can diagnose the problem.