Panel upgrade · Subpanel
Subpanel Install Cost
Plan-level cost for adding an electrical subpanel — feeder run, breaker box, grounding/bonding, and the cases where a subpanel is the right answer vs. a main panel upgrade.
Quick answer: $800–$2,400 for a short run; $1,500–$4,500 for long runs to detached structures. A subpanel does NOT increase total service capacity — confirm your main panel has spare amperage first.
Estimated installed cost
$3,100
Typical range $1,850 – $5,925 · 100A → 200A panel upgrade
Low
$1,850
Best case
Mid
Typical$3,100
Typical
High
$5,925
Worst case
Itemized cost breakdown
Click a row for math & sources| Line item | Low | Mid | High |
|---|---|---|---|
| $700 | $1,100 | $1,700 | |
State labor multiplier applied (CA). | $1,093 | $1,562 | $2,187 |
| $150 | $300 | $600 | |
Reflects installation difficulty, home type, and timing. | $0 | $148 | $1,449 |
| Total | $1,850 | $3,100 | $5,925 |
- Is this a panel replacement, service upgrade, or subpanel install?
- Is utility coordination and disconnect/reconnect included?
- Is the meter and main being replaced?
- Is grounding and bonding work included to current code?
- Will this support future EV charging and heat pump loads?
- Are smart load management devices an alternative to a full upgrade?
- Is permit and inspection included, and how long is the typical wait?
- What is the warranty on labor and the panel itself?
- Will any drywall repair, paint, or fire patching be needed?
- How long will my power be off during the upgrade?
Next step: how to vet a contractor & compare bids
What can change this price
- Estimates are planning ranges, not contractor quotes. Actual prices depend on your home, local labor rates, equipment, code requirements, utility rules, and contractor availability.
Actual prices depend on your home, local labor rates, equipment selection, code requirements, utility rules, and contractor availability. Estimates are planning ranges, not contractor quotes.
- BLS OEWS — Electricians (47-2111)— U.S. Bureau of Labor Statistics, reviewed 2026-05-01
See the single most-likely cost and the realistic range it falls in — not just a low/high band.
- ~30%Service mast, weatherhead, or meter base also replaced+$500–$2,500
- ~25%Grounding & bonding brought to current NEC (ground rods, water bond)+$200–$1,200
- ~15%Knob-and-tube or aluminum branch wiring found (older home)+$1,500–$6,000
- PossibleUtility disconnect / reconnect scheduling and permit fees+$150–$800
Surprise odds are approximate planning estimates, not measured rates; cost ranges are sourced where shown. How this works.
Method: each cost line is drawn from a triangular distribution and correlated by a shared market factor (~0.5), then sampled across 10,000 outcomes (a Monte Carlo simulation); the most-likely value and range emerge from the simulation, not the band. A planning simulation, not a quote.
Frequently asked questions
How much does it cost to add a subpanel?
Most residential subpanel adds run $800–$2,400 installed when the main panel has spare amperage and the run is short. Long conduit runs (50+ ft, detached structures, trenched runs to garages or workshops) push the total to $1,500–$4,500. The work is usually a half-day for an electrician.
When does a subpanel make sense vs. upgrading the main panel?
A subpanel is the right answer when (1) you need more breaker slots but have spare capacity on the main, (2) you're feeding a detached structure (garage, workshop, ADU), or (3) you want to consolidate a circuit zone (kitchen, basement, EV charger area) for code/logistics reasons. It is NOT a substitute for a main panel upgrade if your service amperage is insufficient — adding a subpanel to a 100A main does not give you more total capacity.
Can I add a subpanel without a permit?
No. Subpanel work is permitted electrical work in every U.S. jurisdiction. Pulling a permit triggers an inspection that confirms wire sizing, grounding/bonding, breaker compatibility, and feeder neutral isolation (NEC 250.32 for detached structures). Skipping it creates insurance, resale, and safety problems.
What size subpanel do I need?
For a typical residential add: a 60A or 100A subpanel covers most use cases including an EV charger + a couple of large appliances. Workshops with welders or large compressors may want 100A or 125A. For detached structures, size the subpanel and feeder to the calculated load per NEC 220.83 plus reasonable future-proofing. Your electrician will spec the right amperage.