Wire Sizing

What Size Wire for 200 Amp 100 Feet Away

Pre-calculated NEC-compliant wire size for 200 amps at 100 feet on a 240V single-phase circuit. Immediate answer below.

Recommended Wire Size

Copper

3/0 AWG

Voltage drop: 1.28% (3.06V)

Voltage at load: 236.9V

Controlling factor: Ampacity (NEC 310.16)

Aluminum

250 kcmil

Voltage drop: 1.41% (3.39V)

Voltage at load: 236.6V

Controlling factor: Ampacity (NEC 310.16)

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 Size	Ampacity	V-Drop (V)	V-Drop (%)	V at Load
14 AWG	15A	125.6V	52.33%	114.4V
12 AWG	20A	79.2V	33%	160.8V
10 AWG	30A	49.6V	20.67%	190.4V
8 AWG	50A	31.12V	12.97%	208.9V
6 AWG	65A	19.64V	8.18%	220.4V
4 AWG	85A	12.32V	5.13%	227.7V
3 AWG	100A	9.8V	4.08%	230.2V
2 AWG	115A	7.76V	3.23%	232.2V
1 AWG	130A	6.16V	2.57%	233.8V
1/0 AWG	150A	4.88V	2.03%	235.1V
2/0 AWG	175A	3.87V	1.61%	236.1V
3/0 AWGREC	200A	3.06V	1.28%	236.9V
4/0 AWG	230A	2.43V	1.01%	237.6V
250 kcmil	255A	2.06V	0.86%	237.9V
300 kcmil	285A	1.72V	0.72%	238.3V
350 kcmil	310A	1.47V	0.61%	238.5V
400 kcmil	335A	1.28V	0.53%	238.7V
500 kcmil	380A	1.03V	0.43%	239V

Table shows all standard AWG/kcmil sizes for 200A at 100 ft on 240V (copper). Green check = meets both ampacity and 3% voltage drop. REC = smallest compliant size.

Key Considerations

A 200 amp service at 100 feet typically requires large conductors where voltage drop becomes the controlling factor rather than ampacity. Consider parallel runs of smaller conductors if the required size exceeds what fits in available conduit.

For aluminum conductors at this amperage, ensure all terminations use AL-CU rated lugs and apply anti-oxidant compound. Aluminum is significantly cheaper for large feeders and is standard practice for service entrance conductors.

Frequently Asked Questions

What size wire do I need for a 200 amp service at 100 feet?▾

For a 200A/240V circuit at 100 feet, use 3/0 AWG copper (1.28% drop) or 250 kcmil aluminum. This keeps voltage drop within the NEC-recommended 3% limit.

Can I use aluminum wire for a 200 amp circuit?▾

Yes. Aluminum wire is a cost-effective alternative for larger circuits. For 200A at 100 feet, use 250 kcmil aluminum (1.41% 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 200A 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.

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What Size Wire for 200 Amp 300 Feet Away

200A / 400 ft

What Size Wire for 200 Amp 400 Feet Away

Need a Custom Calculation?

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

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