Updated October 2026
Quick answer
Subpanel installation in Oklahoma City means a smaller breaker panel fed from the main panel by a feeder, placed where new circuits are needed: a garage or shop, a remodeled kitchen, an addition or a detached building. We run a load calculation to confirm the main service can carry the new loads, size the feeder and subpanel, keep neutral and ground separated as code requires, and file the permit.
Space versus capacity
What a subpanel install involves
A full main panel with no open slots is one of the most common reasons we are called about subpanels. A subpanel solves the space problem: a feeder breaker in the main panel supplies a new panel with room for many more circuits, placed close to where they are needed. That shortens circuit runs to a garage, a shop or a new kitchen, and keeps the main panel from turning into a nest of tandem breakers.
What a subpanel cannot do is add service capacity. If the house is already near the limit of its 100 or 150 amp service, adding a shop with a welder and a compressor may need a service upgrade instead of, or as well as, a subpanel. We run the numbers before recommending either, then size the feeder, choose the subpanel, and wire it with the separated neutral and ground bars that subpanels require.
Choosing between the options
Subpanel, upgrade or both
| Option | Solves | Does not solve |
|---|---|---|
| Subpanel | Breaker space near the new circuits | Service capacity |
| Service upgrade | Capacity for the whole house | Long circuit runs to far rooms |
| Subpanel plus upgrade | Both space and capacity | Largest project |
| Tandem breakers | A few extra spaces where listed | Anything beyond a couple of circuits |
What moves the price
What sets the price of a subpanel
- Feeder size and length Larger and longer feeders cost more.
- Subpanel size More spaces and a larger rating cost more.
- Location A garage wall beside the main panel is quick; a detached building needs trenching.
- Grounding electrode Required at detached buildings.
- Main panel room A feeder breaker needs space in the main panel.
- Circuits added Each new circuit in the subpanel adds labor.
- Permit and inspection Required for subpanel work.
2026 cost guides put a subpanel at about $2,800 to $5,100 installed, with each new circuit around $200 to $900. National planning ranges, not our price.
Sub-jobs this page covers
Garages, remodels and detached buildings
Garage or shop subpanel
A garage or shop that will run a compressor, a table saw, a welder or a mini-split needs more circuits than one or two runs from the house panel can provide. A subpanel in the garage gives each tool its own breaker, puts shutoffs where the work happens, and makes future additions easy. We size the feeder for the tools you have and the ones you plan to buy, place the panel where it stays accessible and clear of workbenches, and label every breaker.
Kitchen remodel subpanel
A remodeled kitchen can add six or more circuits, and a main panel across the house may have no room for them. A subpanel near the kitchen shortens every run and keeps the kitchen circuits together. We confirm the service can carry the new appliances, set the subpanel in a utility room, pantry or garage wall where code allows access, and feed it from the main panel. The kitchen circuits land in the subpanel with AFCI and GFCI protection as required.
Detached building feeder
A detached garage, barn or shop fed from the house needs a feeder sized for its load and the distance, run underground in conduit or cable at code depth, and a subpanel at the building with its own grounding electrode. The neutral and ground stay separated in that subpanel, which is where many older outbuilding installs are wrong. We trench, run, set the panel, drive the ground rod and have the whole thing inspected before the building is energized, and leave spare spaces for circuits you add later.
Oklahoma City conditions
Full panels in Oklahoma City homes
Many older Oklahoma City homes were wired when a house needed far fewer circuits than a modern kitchen, a shop and an EV charger demand today, so their panels ran out of spaces long ago. Before recommending a subpanel we calculate what the existing service can actually carry, because in some older houses the honest answer is a service upgrade, and a subpanel alone would only move the problem somewhere else.
DIY or call
Why subpanel wiring trips up DIY installs
| Task | Homeowner-safe? | What goes wrong |
|---|---|---|
| Plan the tools and circuits you need | Yes | Nothing, it helps |
| Mount plywood backing for the panel | Yes | Nothing |
| Run the feeder | No | Undersized for load or distance |
| Wire the subpanel | No | Neutral and ground bonded together |
| Add breakers later | No | Wrong breaker type for the panel |
Step by step
From the load calculation to the labeled panel
- Load calculation
What the service can carry with the new loads.
- Choose subpanel or upgrade
Explained plainly with the numbers.
- Run the feeder
From the main panel, underground for detached buildings.
- Set and wire the subpanel
Neutral and ground separated, electrode where required.
- Inspect and label
Inspected, every breaker labeled.
Questions we get about this job
Subpanel questions
No. It adds breaker space, not service capacity. A load calculation tells us if the service is enough.
It depends on the load. Space alone points to a subpanel; capacity problems point to an upgrade.
Yes. A detached building with a feeder needs its own grounding electrode.
Code requires them bonded only at the main service, so fault current follows the right path.
Yes, if the service capacity allows it.
Yes. It is permitted and inspected.
A garage subpanel beside the main panel usually takes a day; a detached building feeder takes longer.
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Call for a load calculation. We tell you whether a subpanel, an upgrade or both is the right answer before any work is quoted.