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What Size Wire for 200 Amps at 300 Feet?

At 300 ft, the default 200 A answer moves deeper into long-run sizing: 250 kcmil copper or 400 kcmil aluminum, with voltage drop governing both materials.
Load
200 A
Distance
300 ft
Band
200 A feeder / service
Defaults
Non-continuous, 75 C lugs, 86 F, 240 V single-phase

Computed Starting Point

Ampacity and voltage drop under common defaults for this amp and distance.

MaterialComputed sizeOCPDUsable ampacityGoverning constraintDefault check
Copper250 kcmil200 A255 AVoltage dropPasses defaults
Aluminum400 kcmil200 A270 AVoltage dropPasses defaults
What Size Wire for 200 Amps at 300 Feet? under common non-continuous defaults: THHN or XHHW-2 insulation, 75 C terminations, 86 F ambient, 240 V single-phase and no more than three current-carrying conductors.

What 300 ft ChangesAt 300 ft, both materials are past the short-run platform and the first 250 ft jump. The page is a route-certainty and equipment-planning checkpoint between the 250 ft result below it and the 400 ft result above it.

Run the wire size calculatorCheck voltage drop alone

Zero-Length vs This Distance

If the distance-adjusted size is larger, voltage drop governed under these defaults.

CaseCopper sizeCopper constraintAluminum sizeAluminum constraint
Ampacity only (0 ft)3/0 AWGTermination rated 75 C250 kcmilTermination rated 75 C
300 ft (this page)250 kcmilVoltage drop400 kcmilVoltage drop
Copper and aluminum sizes for 200 A with no distance entered versus 300 ft one-way.

Adjacent Distances at This Amp

Neighboring published lengths for 200 A under the same defaults.

DistanceCopper sizeAluminum sizeCopper constraint
250 ft4/0 AWG300 kcmilVoltage drop
300 ft (this page)250 kcmil400 kcmilVoltage drop
400 ft300 kcmil500 kcmilVoltage drop
200 A copper and aluminum starting sizes across neighboring distance pages.

300 ft Is the Middle Long-Run Jump

200 A feeder / service context for 200 A at 300 ft.

A 300 ft 200 A search usually means a detached shop, barn, equipment pad, remote panel or long driveway route where the conductor path is already a design decision. Small layout changes can move the project into a different neighboring page.

This is not the first 200 A voltage-drop jump; 250 ft already moved up. At 300 ft, copper leaves AWG sizing for 250 kcmil, and aluminum moves to 400 kcmil under the same defaults.

What Changes This Long-Run Answer

Checks that matter for distance-governed sizing in this amp band.

  • Choose between 250, 300 and 400 ft

    Use the measured one-way path rather than a rounded site distance. The neighboring 200 A pages show different conductor landings at each step.

  • Rerun for load below 200 A

    If the actual sustained load is below the panel or service rating, voltage drop may not require the same conductor size.

  • Keep input defaults visible

    A 120 V load, three-phase system, hotter ambient, continuous load or extra current-carrying conductors should be checked in the calculator instead of borrowed from this page.

  • Confirm physical fit

    250 kcmil copper and 400 kcmil aluminum affect raceway, pull planning, bend space and terminations. Treat those as part of the sizing decision.

200 A at 300 ft FAQs

What size wire for 200 amps at 300 feet?
Under the defaults on this page, start with 250 kcmil copper or 400 kcmil aluminum. Voltage drop governs both results.
Why is 300 ft different from 250 ft?
At 250 ft, the default result is 4/0 copper or 300 kcmil aluminum. At 300 ft, the same assumptions move to 250 kcmil copper or 400 kcmil aluminum.
Can I use the 250 ft result for a 300 ft route?
Not under these defaults. A measured 300 ft one-way path lands on larger conductors than the 250 ft page.
Is 300 ft automatically too long for 200 A?
No. The displayed defaults still return a passing result, but the actual load, route, voltage and equipment constraints can change the answer.