6 Wire Ampacity & Specifications
NEC ampacity, resistance and typical uses for 6 copper and aluminum wire.
Calculations are built on the 2023 National Electrical Code (NEC) and cross-checked against the published code tables. How we verify. Last reviewed June 2026.
Copper 75°C
65A
Copper 90°C
75A
Aluminum 75°C
50A
Typical breaker
60A
6 Wire Specifications
| Ampacity — Copper (60 / 75 / 90°C) | 55 / 65 / 75 A |
| Ampacity — Aluminum (60 / 75 / 90°C) | 40 / 50 / 55 A |
| Cross-section | 26,240 circular mils |
| DC resistance — Copper | 0.491 Ω / 1000 ft |
| DC resistance — Aluminum | 0.808 Ω / 1000 ft |
| Typical voltage drop (240V) | 1.2% at 50 ft · 2.5% at 100 ft (at 60A) |
Common Uses for 6 Wire
- 55–65A circuits — 50A spas, 60A sub-panels, large EV
- Detached garage and shop feeders
Ampacities are from NEC Table 310.16. 14, 12 and 10 AWG are limited to 15A, 20A and 30A overcurrent protection (240.4(D)). Terminations rated 60°C or 75°C usually cap the usable ampacity below the 90°C value.
Sizing a circuit?
Use the calculator to size wire for your current, distance and voltage.