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What Size Wire for 50 Amps at 100 Feet?

At 100 ft, the default 50 A answer has already moved beyond ampacity-only sizing: 6 AWG copper or 4 AWG aluminum, with voltage drop governing both materials.
Load
50 A
Distance
100 ft
Band
Mid branch / light feeder
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
Copper6 AWG50 A65 AVoltage dropPasses defaults
Aluminum4 AWG50 A65 AVoltage dropPasses defaults
What Size Wire for 50 Amps at 100 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 100 ft ChangesAt 100 ft, the result moves from 8 AWG copper and 6 AWG aluminum at zero length to 6 AWG copper and 4 AWG aluminum. The breaker is still 50 A; the larger conductor is buying voltage-drop margin under the stated defaults.

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)8 AWGTermination rated 75 C6 AWGTermination rated 75 C
100 ft (this page)6 AWGVoltage drop4 AWGVoltage drop
Copper and aluminum sizes for 50 A with no distance entered versus 100 ft one-way.

Adjacent Distances at This Amp

Neighboring published lengths for 50 A under the same defaults.

DistanceCopper sizeAluminum sizeCopper constraint
100 ft (this page)6 AWG4 AWGVoltage drop
150 ft4 AWG3 AWGVoltage drop
50 A copper and aluminum starting sizes across neighboring distance pages.

100 ft Is the First 50 A Distance Page

Mid branch / light feeder context for 50 A at 100 ft.

A 50 A run at 100 ft is often an EVSE branch circuit, small shop feeder, detached-garage feed, welder outlet, or longer equipment circuit. The common mistake is to start from the short-circuit conductor and ignore the measured path.

Under the defaults on this page, both materials are already larger than the zero-length ampacity result. That makes 100 ft the first 50 A page where the user should treat distance as part of the conductor choice.

What Changes This Long-Run Answer

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

  • Measure the one-way path

    Count the route through walls, trench, risers and equipment offsets. A guessed 100 ft run can land closer to the 150 ft page.

  • Do not raise the breaker

    The distance-driven upsize does not authorize more than the intended 50 A overcurrent device, and grounding conductor sizing should be checked after a drop-driven conductor increase.

  • Confirm 240 V assumptions

    These defaults assume 240 V single-phase. A 120 V load at the same current and distance needs its own calculator run.

  • Check aluminum terminations

    4 AWG aluminum can be attractive on cost, but only if the equipment lugs and installation method accept the material and size.

50 A at 100 ft FAQs

What size wire for 50 amps at 100 feet?
Under the defaults on this page, start with 6 AWG copper or 4 AWG aluminum. Voltage drop governs both distance-adjusted results.
Why is 100 ft larger than the short 50 A wire size?
The zero-length comparison is 8 AWG copper or 6 AWG aluminum, but the 100 ft voltage-drop check pushes both materials larger under these defaults.
Can I use the 100 ft answer if the route may be 150 ft?
Do not guess upward or downward. The 150 ft page moves to 4 AWG copper and 3 AWG aluminum under the same defaults.
Does upsizing wire make this more than a 50 A circuit?
No. The displayed result still uses a 50 A overcurrent device; the larger conductor addresses voltage drop under the page assumptions.