1/0 AWG Wire Ampacity & Specifications
1/0 AWG copper wire carries 150A at 75°C (NEC Table 310.16), or 120A for aluminum; copper is typically protected by a 150A breaker.
Calculations are built on the 2023 National Electrical Code (NEC) and cross-checked against the published code tables. How we verify. Last updated June 2026.
1/0 AWG wire has an ampacity of 150A at 75°C for copper and 120A for aluminum (NEC Table 310.16). Its 60°C and 90°C copper ratings are 125A and 170A. Copper 1/0 AWG is commonly protected by a 150A breaker.
Copper 75°C
150A
Copper 90°C
170A
Aluminum 75°C
120A
Copper breaker (75°C)
150A
1/0 AWG Wire Specifications
| Ampacity — Copper (60 / 75 / 90°C) | 125 / 150 / 170 A |
| Ampacity — Aluminum (60 / 75 / 90°C) | 100 / 120 / 135 A |
| Cross-section | 105,600 circular mils |
| DC resistance — Copper | 0.122 Ω / 1000 ft |
| DC resistance — Aluminum | 0.201 Ω / 1000 ft |
| Typical voltage drop (240V) | 0.8% at 50 ft · 1.5% at 100 ft (at 150A) |
Common Uses for 1/0 AWG Wire
- 125–150A services and feeders
- 150A copper feeders
Ampacities are from NEC Table 310.16. Copper 14, 12 and 10 AWG are limited to 15A, 20A and 30A overcurrent protection, aluminum 12 and 10 AWG to 15A and 25A (240.4(D)). Terminations rated 60°C or 75°C usually cap the usable ampacity below the 90°C value.
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