Quick answer
A branch circuit is the part of a home’s wiring that runs from the final breaker or fuse protecting it to the outlets, lights or appliances it serves.
The NEC defines it as the circuit conductors between the final overcurrent device and the outlet(s). Each breaker in your panel starts one branch circuit. Its amp rating comes from that breaker, not from the wire.
Quick facts
The key facts about Branch Circuit, with sources:
Key takeaways
- A branch circuit starts at a breaker and ends at the outlets, lights or appliance it feeds.
- Its rating is the breaker’s rating. A 20 A breaker makes a 20 A branch circuit.
- The NEC requires certain circuits in homes: kitchen small-appliance, laundry, bathroom and garage.
- The load on a branch circuit may never exceed its ampere rating, per 2023 NEC 210.23.
- A branch circuit for just one appliance is called an individual or dedicated circuit.
What a branch circuit is
Power arrives at your main panel through the service. From there it splits into many smaller runs, like branches off a tree trunk. Each run is a branch circuit.
The National Electrical Code gives the formal definition: the circuit conductors between the final overcurrent device protecting the circuit and the outlet(s) 1. “Overcurrent device” means a breaker or fuse.
“Final” matters: a run from the main panel to a garage or basement subpanel is a feeder, and the branch circuits begin at the subpanel’s breakers.
An “outlet” in code language is any point where power is taken off: a receptacle, a light fixture box or a hard-wired appliance.
How a branch circuit is rated and loaded
The 2023 NEC 210.18 says a branch circuit is rated by the maximum ampere rating or setting of its overcurrent device. If heavier wire is used for any reason, the breaker still sets the rating 2. So 12 AWG wire on a 15 A breaker is a 15 A circuit.
The 2023 NEC 210.23 sets the loading rule: in no case shall the load exceed the branch-circuit ampere rating 3. It also lists what each size may feed.
A new 10 A circuit may supply lighting outlets and some exhaust fans, but not receptacle outlets, fixed appliances, garage door openers or laundry equipment 3.
- ServiceUtility conductors to the main breaker
- FeedersMain panel to any subpanel
- Branch circuitsFinal breaker to outlets, per the NEC definition 1
- Outlets and loadsReceptacles, lights, appliances
Source: [1]
Types of branch circuits
| Type | What it serves | Typical rating |
|---|---|---|
| General-purpose | Several outlets and lights in rooms | 15 or 20 A, 120 V |
| Small-appliance | Kitchen, dining and pantry receptacles | 20 A, 120 V; two or more required 5 |
| Laundry | Laundry receptacle outlets only | 20 A, 120 V 5 |
| Bathroom | Bathroom receptacle outlets | 20 A, 120 V 5 |
| Garage | Garage receptacle outlets | At least one 20 A, 120 V 4 |
| Individual (dedicated) | One appliance only | Sized to the appliance |
| Lighting (new in 2023) | Lighting outlets, some fans | 10 A; no receptacles 2 |
| Multiwire | Two hots sharing one neutral | Common for kitchen small-appliance circuits 5 |
Example: the required circuits in a typical kitchen-laundry-bath layout
Counts below are the code minimums described for NEC 210.11(C) by EC&M and the 2023 garage text 5 4. Many homes have more.
| Area | Minimum required | What else it may serve |
|---|---|---|
| Kitchen and dining receptacles | Two or more 20 A, 120 V small-appliance circuits | No lighting or receptacles in other areas 5 |
| Laundry | One 20 A, 120 V circuit | More than one laundry receptacle; no lighting 5 |
| Bathroom | One 20 A, 120 V circuit for receptacles | One bathroom’s outlets all on it, if no fixed load over 10 A 5 |
| Garage | At least one 20 A, 120 V circuit | Outdoor receptacles; a one-bay garage’s other outlets 4 |
- 2+Kitchen small-applianceNEC 210.11(C)(1)
- 1LaundryNEC 210.11(C)(2)
- 1BathroomNEC 210.11(C)(3)
- 1+GarageNEC 210.11(C)(4)
Minimum total in this layout: five 20 A circuits before lighting, bedrooms, HVAC or any 240 V appliance. Use the appliance circuit lookup for the rest.
Where branch circuits appear in your paperwork
In the panel directory. The 2023 NEC 408.4 requires a clear, permanent description of every circuit, specific to its use 6. Each line is one branch circuit.
On an electrician’s quote: “add 20 A 120 V circuit for microwave,” “new 50 A 240 V branch circuit for range.” On permit drawings: a panel schedule listing each circuit’s breaker, wire and load.
Why the branch-circuit system works
Benefits
Drawbacks
- Older homes often have too few circuits for modern loads.
- Adding branches needs panel space.
- Poorly labeled branches make the panel confusing.
Limits of a branch circuit
A branch circuit can carry only its rating. Plugging a power strip into a kitchen outlet does not create capacity. It just puts more load on the same breaker.
Older homes may predate the kitchen, laundry, bath and garage rules. They are not illegal for that alone, since code generally applies to new work. But they are more likely to trip and may be due for upgrades during a remodel.
Garage rules show how the code keeps shifting. The 2017 NEC first required a 20 A garage receptacle circuit, because garage tools and appliances often draw 12 to 16 amps, too much for a shared 15 A circuit 4.
The 2020 and 2023 editions then clarified what that circuit may and may not feed 4. A garage wired before those rules is not wrong for its time, but it may struggle with today’s tools.
What drives the cost of branch circuit work
No prices here. These drive the cost; see the project cost tool.
- Number of circuits added in one visit.
- Distance and access from the panel.
- Protection required, such as GFCI or AFCI breakers.
- Panel space, or the need for a subpanel.
- Wall repair after fishing wire in finished rooms.
- Lifespan. Wiring lasts decades when not overloaded; devices such as receptacles and GFCIs wear sooner.
How a branch circuit gets added
- The electrician lists the loads and picks the rating.
- Checks panel space and runs a load calculation if the load is big.
- Pulls a permit; see electrical permits explained.
- Runs wire, sets boxes, installs devices and the breaker.
- Labels the directory, tests and passes the rough-in and final inspections.
Looking after your branch circuits
- Keep the directory accurate after any change.
- Spread heavy kitchen appliances across both small-appliance circuits.
- Test GFCI protection monthly.
- Note circuits that trip often and tell your electrician.
Branch circuit risks and warning signs
Overloaded or damaged branch circuits are a fire source. The CPSC estimates about 17,100 home fires a year from electrical distribution equipment in 2019 to 2021 7. Warm outlets, scorch marks, flicker and frequent trips are warning signs.
Another common fault: a breaker too large for its wire, often after someone “fixed” nuisance trips. The CPSC warns that oversizing fuses is a serious fire hazard 8; the same logic applies to breakers.
Never upsize a breaker to stop trips
The breaker protects the wire. A bigger breaker on the same wire lets the wire overheat inside the wall. Call an electrician to find the real cause.
Code rules for branch circuits
NEC Article 210 covers branch circuits. Key sections in the 2023 edition: 210.11(C) required dwelling circuits 5 4, 210.18 ratings 2, 210.19 conductor sizing 1 and 210.23 permissible loads 3.
The 2026 edition is free to read online 9 and revises parts of 210, such as GFCI classes and AFCI rules for extended circuits 10.
Your jurisdiction’s adopted edition is what the inspector enforces.
Branch circuit vs related terms
| Term | Runs from | Runs to |
|---|---|---|
| Branch circuit | Final breaker or fuse 1 | Outlets and loads |
| Dedicated circuit | One breaker | One appliance |
| Feeder | Main panel | Subpanel |
| Service conductors | Utility connection | Main breaker |
| Electrical circuit | Any source | Any load and back |
Myths about branch circuits
- Myth Thicker wire raises the circuit rating.
- Reality The breaker sets the rating, per 2023 NEC 210.18 2.
- Myth Bathroom lights can share the bathroom receptacle circuit anywhere.
- Reality Only in a single bathroom with no fixed load over 10 A; otherwise the circuit serves receptacles only 5.
- Myth Every outlet needs its own circuit.
- Reality General outlets share circuits; only certain appliances need their own.
What changes by state
Branch-circuit rules depend on the NEC edition your state or city adopted. A state still on the 2020 edition does not allow the 10 A lighting circuits added in 2023 2, and the 2026 changes apply only after adoption. Licensing for who may add circuits also differs.
When branch circuits matter to you
Branch circuits matter when you remodel a kitchen, bath or laundry, finish a garage, or keep tripping one breaker. Ask your electrician which circuits the plan adds and how each is protected. For whole-home capacity, see the load calculator.
Ask for the panel schedule
On any remodel, ask the electrician for an updated panel schedule. It shows every branch circuit, its breaker and what it serves.
Questions about Branch Circuit
What is a branch circuit?
A branch circuit is the wiring between the final breaker or fuse and the outlets it serves. The NEC defines it as the circuit conductors between the final overcurrent device protecting the circuit and the outlet(s). Each breaker in your panel starts one.
What is the difference between a branch circuit and a feeder?
A feeder carries power from the main panel to another panel, such as a subpanel. A branch circuit starts at the final breaker and goes to outlets, lights or appliances. Feeders feed panels; branch circuits feed loads.
What are the standard branch circuit sizes?
For circuits serving more than one outlet, the 2023 NEC 210.18 lists 10, 15, 20, 30, 40 and 50 amps. The 10 A size is new in 2023 and may not feed receptacles. Individual circuits for one appliance can be other sizes.
How many branch circuits does a kitchen need?
At least two 20-amp, 120-volt small-appliance circuits for the counter and dining receptacles, under NEC 210.11(C)(1). Fixed appliances such as a dishwasher, disposal, microwave or range usually get their own circuits too.
Does a bathroom need its own circuit?
Yes. The NEC requires at least one 20-amp, 120-volt circuit for bathroom receptacles. It cannot feed other outlets, except that one 20-amp circuit may supply everything in a single bathroom if no fixed load is over 10 amps.
What is an individual branch circuit?
It is a branch circuit that supplies only one piece of equipment, often called a dedicated circuit. Ranges, dryers, water heaters, EV chargers and many HVAC units use them.
Can I put lights and outlets on the same branch circuit?
On general-purpose 15 or 20 amp circuits, yes. The 2023 NEC 210.23 lets them supply lighting outlets and other equipment together. The kitchen small-appliance, laundry and bathroom circuits are the main exceptions.
What is a multiwire branch circuit?
It is two hot wires sharing one neutral, supplying two 120-volt circuits with fewer wires. The NEC allows kitchen small-appliance circuits to be one multiwire circuit. Both hots must be shut off together for work, which is why they use a tied breaker handle.
Who decides how many branch circuits a house has?
The code sets minimums, and the electrician designs the rest around your loads. The inspector checks the work against your jurisdiction’s adopted NEC edition. A load calculation confirms the service can carry them all.
Why do garages need a 20 amp circuit?
Because garage tools and appliances often draw 12 to 16 amps, which is too much for a typical 15-amp circuit that also feeds the garage light. The 2017 NEC added the 20-amp garage circuit rule for that reason, and the 2023 edition clarified it.
Sources
- NEC 2023 210.19 Conductors: Minimum Ampacity and Size (includes branch circuit definition), ElectricalLicenseRenewal.com, retrieved .
- NEC 2023 210.18 Branch Circuit Rating, ElectricalLicenseRenewal.com, retrieved .
- NEC 2023 210.23 Permissible Loads, Multiple-Outlet Branch Circuits, ElectricalLicenseRenewal.com, retrieved .
- NEC 2023 210.11(C)(4) Garage Branch Circuits, ElectricalLicenseRenewal.com, retrieved .
- EC&M, Code Q&A: Additional Branch Circuit Requirements for Dwelling Units, retrieved .
- NEC 2023 408.4(A) Circuit Directory or Circuit Description, ElectricalLicenseRenewal.com, retrieved .
- U.S. CPSC, 2019–2021 Residential Fire Loss Estimates (May 2024), retrieved .
- U.S. CPSC, CPSC and NESF Urge Consumers to Plug Into Electrical Safety (2000), retrieved .
- NFPA 70, National Electrical Code, 2026 edition (free access), retrieved .
- Minnesota Dept. of Labor and Industry, NEC 2026 Adoption Review Committee minutes, 25 Sept 2025, retrieved .
Expert review
Written by the HyreElectrical Research team. Not yet reviewed by an outside expert. We say so rather than imply a review that has not happened; see our editorial policy.
How the numbers were checked: Definition and rating rules from 2023 NEC text reproduced in code-change summaries; dwelling circuit requirements from EC&M Code Q&A (edition not stated there) and the 2023 garage text; fire figures from CPSC.
Suggest a correction. We fix errors and say what changed.