Wire Sizing

Wire Size for 50 Amp EV Charger 100 Feet

Pre-calculated NEC-compliant wire size for 50 amps at 100 feet on a 240V single-phase circuit. Immediate answer below.

Recommended Wire Size

Copper
6 AWG
Voltage drop: 2.05% (4.91V)
Voltage at load: 235.1V
Controlling factor: Voltage Drop (3% limit)
Aluminum
4 AWG
Voltage drop: 2.12% (5.08V)
Voltage at load: 234.9V
Controlling factor: Voltage Drop (3% limit)

Based on NEC Table 310.16 (75°C column), single-phase, 240V, 3% max voltage drop, one-way distance 100 ft.

Wire Comparison Table

Wire SizeAmpacityV-Drop (V)V-Drop (%)V at LoadStatus
14 AWG15A31.4V13.08%208.6V
12 AWG20A19.8V8.25%220.2V
10 AWG30A12.4V5.17%227.6V
8 AWG50A7.78V3.24%232.2V
6 AWGREC65A4.91V2.05%235.1V
4 AWG85A3.08V1.28%236.9V
3 AWG100A2.45V1.02%237.6V
2 AWG115A1.94V0.81%238.1V
1 AWG130A1.54V0.64%238.5V
1/0 AWG150A1.22V0.51%238.8V
2/0 AWG175A0.97V0.4%239V
3/0 AWG200A0.77V0.32%239.2V
4/0 AWG230A0.61V0.25%239.4V
250 kcmil255A0.52V0.21%239.5V
300 kcmil285A0.43V0.18%239.6V
350 kcmil310A0.37V0.15%239.6V
400 kcmil335A0.32V0.13%239.7V
500 kcmil380A0.26V0.11%239.7V

Table shows all standard AWG/kcmil sizes for 50A at 100 ft on 240V (copper). Green check = meets both ampacity and 3% voltage drop. REC = smallest compliant size.

Key Considerations

EV chargers are continuous loads under NEC Article 625. The conductor must be sized for 125% of the rated current (50A x 1.25 = 62.5A) when selecting breaker size. The voltage drop calculation above uses the actual draw of 50A.

Install a dedicated circuit with no other loads. Use THHN/THWN-2 conductors rated for 75°C or higher. All connections at the panel and EVSE must be torqued to manufacturer specifications.

Frequently Asked Questions

What size wire do I need for a EV charger at 100 feet?
For a 50A/240V circuit at 100 feet, use 6 AWG copper (2.05% drop) or 4 AWG aluminum. This keeps voltage drop within the NEC-recommended 3% limit.
Can I use aluminum wire for a 50 amp circuit?
Yes. Aluminum wire is a cost-effective alternative for larger circuits. For 50A at 100 feet, use 4 AWG aluminum (2.12% voltage drop). Aluminum requires AL-rated connectors and anti-oxidant compound at all terminations.
What happens if the voltage drop exceeds 3%?
Voltage drop above 3% reduces equipment efficiency, can cause motors to overheat, and may violate NEC 210.19(A) Informational Note No. 4. For a 50A circuit at 100 feet on 240V, exceeding 3% means the load receives less than 232.8V, which can damage sensitive electronics and shorten appliance lifespan.

Need a Custom Calculation?

Different voltage, three-phase, or custom max drop percentage? Use our interactive calculator.

Wire Size Calculator