Wire size for 50 amps by distance (240 V, 3% drop)
| One-way distance | Copper | Drop | Aluminum |
|---|---|---|---|
| 25 ft | 8 AWG | 0.80% | 6 AWG |
| 50 ft | 8 AWG | 1.59% | 6 AWG |
| 75 ft | 8 AWG | 2.39% | 6 AWG |
| 100 ft | 6 AWG | 2.05% | 4 AWG |
| 150 ft | 4 AWG | 1.93% | 3 AWG |
| 200 ft | 4 AWG | 2.57% | 2 AWG |
| 250 ft | 3 AWG | 2.55% | 1 AWG |
| 300 ft | 2 AWG | 2.43% | 1/0 AWG |
Single-phase 240 V, 75°C terminals, non-continuous load. For continuous loads (3+ hours) size for 62 A.
Common 50 A circuits
50 amp circuits typically feed ranges, EV chargers and hot tubs. The breaker protects the wire, so never pair a 50 A breaker with wire rated below 50 A.
Frequently asked questions
Can I use 6 AWG wire on a 50 amp breaker?
Yes. 6 AWG copper is rated at least 50 A even in the 60°C column, so it works for NM-B cable and THHN alike, as long as voltage drop is acceptable.
How far can I run 8 AWG wire at 50 amps?
At 240 V with a 3% voltage-drop limit, about 75 ft one way. Beyond that, go up one size.