Skip to content
ElectraKit
Open menu

What Size Wire for 200 Amps?

For 200 amps with the displayed 75 C termination defaults, start with 3/0 AWG copper or 250 kcmil aluminum. This common residential service rating needs product, lug, utility, AHJ, and load-calculation checks before it becomes an installation answer.
Load
200 A
Distance
0 ft entered
Band
Service / large feeder
Defaults
Non-continuous, 75 C lugs, 86 F, 240 V single-phase
Conductor count
3 current-carrying

Computed Starting Point

The table uses common defaults. Change the calculator inputs for the actual installation.

MaterialComputed sizeOCPDUsable ampacityGoverning constraintDefault check
Copper3/0 AWG200 A200 ATermination rated 75 CPasses defaults
Aluminum250 kcmil200 A205 ATermination rated 75 CPasses defaults
What Size Wire for 200 Amps? under common non-continuous defaults: THHN or XHHW-2 insulation, 75 C terminations, 86 F ambient, 240 V single-phase, no more than three current-carrying conductors, and 0 ft route length entered.

What 200 A ChangesAt 200 A, the displayed copper row has no extra ampacity above the 200 A rating under 75 C defaults, and aluminum shows only 205 A. Equipment limited to 60 C will force larger conductors, while service-entrance product listings, meter and disconnect lugs, utility standards, and AHJ review can change the allowed conductor.

Run the wire size calculator

Adjacent Amp Ratings

See whether stepping one standard size up or down forces a conductor jump under the same defaults.

LoadCopper sizeCopper OCPDAluminum sizeAluminum OCPD
175 A2/0 AWG175 A4/0 AWG175 A
200 A (this page)3/0 AWG200 A250 kcmil200 A
225 A4/0 AWG225 A300 kcmil225 A
Copper and aluminum starting sizes for 200 A and the neighboring published amp pages, under the same defaults as the result above.

A plateau means neighboring amp ratings share a conductor size under these defaults. A jump means a standard breaker change often needs a larger wire; confirm with your real ambient, length and terminations.

200 A Is the Common Service Rating Check

Service / large feeder context for a 200 A circuit.

A 200 A wire-size search is often a residential service upgrade, meter-main replacement, large subpanel, detached shop feeder, or panel-capacity plan. Because 200 A is a familiar service size, it is easy to skip the harder question: whether the calculated load, service equipment, and utility rules actually support that rating.

Under the displayed 75 C termination defaults, copper moves from 2/0 AWG at 175 A to 3/0 AWG here, while aluminum moves from 4/0 AWG to 250 kcmil. The next 225 A page moves both materials again, so 200 A is a real equipment boundary rather than a generic large-feeder label.

What Changes This Answer

Checks that can change the starting conductor under the displayed defaults.

  • Load calculation before service upgrade

    A 200 A conductor answer assumes 200 A is the correct service or feeder rating. Confirm the dwelling, feeder, or equipment load calculation before selecting wire.

  • Confirm the conductor product

    Service-entrance cable, raceway conductors, and feeder cable assemblies can follow different product listings and termination limits. Match the result to the actual product.

  • Check 60 C equipment limits

    The displayed 3/0 AWG copper and 250 kcmil aluminum results are 75 C defaults. Equipment limited to 60 C will force larger conductors for a full 200 A feeder or service.

  • Do not reuse 175 A conductors

    Under these defaults, 175 A uses 2/0 AWG copper and 4/0 AWG aluminum. This 200 A page moves to 3/0 AWG copper and 250 kcmil aluminum.

  • Coordinate utility and AHJ requirements

    For 200 A residential service work, service-entrance conductor products, meter sockets, service disconnects, utility standards, grounding, bonding, and local review can require a different accepted conductor assembly than the generic starting point.

200 Amp Wire Size FAQs

What size wire for 200 amps?
Under the 75 C non-continuous defaults on this page, start with 3/0 AWG copper or 250 kcmil aluminum. Confirm the exact conductor product, terminal rating, service equipment, load calculation, and utility or AHJ requirements.
Is aluminum OK for a 200 A service?
Aluminum is common for 200 A services and large feeders when the conductor, meter, disconnect, and panel lugs are listed for aluminum and the installation follows the product instructions.
Why does 200 A use larger wire than 175 A?
The adjacent 175 A page shows 2/0 AWG copper and 4/0 AWG aluminum under the same defaults. At 200 A, copper moves to 3/0 AWG and aluminum moves to 250 kcmil.
Can I use this page as final approval for a service?
No. Treat it as a planning starting point. Service work still needs conductor product verification, equipment lug checks, grounding and bonding, utility requirements, AHJ review, and a load calculation.
Why do 200 A service conductor sizes vary?
Residential service-entrance products, meter-main lugs, utility standards, and AHJ rules can use different accepted assemblies than a generic 75 C conductor-in-raceway starting point. Match the result to the product and local requirements.