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How many amps can 1/0 AWG wire carry?

150 A — copper at 75 °C, NEC Table 310.16.

1/0 AWG copper carries 150 A at 75 °C, 125 A at 60 °C and 170 A at 90 °C under NEC Table 310.16, before derating. Aluminum at the same size is 120 A at 75 °C.

Safety first. These figures are an educational reference before derating, not a code substitute. Verify against the current NEC and have circuits reviewed by a licensed electrician.

1/0 AWG ampacity — copper vs aluminum

1/0 AWG ampacity by conductor material and insulation temperature rating.
Material 60 °C 75 °C 90 °C Breaker cap
Copper 125 A 150 A 170 A —
Aluminum 100 A 120 A 135 A —

Values are amps at a 30 °C ambient, before derating for temperature or conductor bundling. Most installations must use the 75 °C column regardless of the wire's own rating, because terminals and breakers are rated 75 °C (NEC 110.14(C)).

How far can you run 1/0 AWG at 150 A?

Ampacity answers whether a conductor will overheat. It says nothing about whether the voltage still arrives at the far end. Past roughly fifty feet, voltage drop is usually what really sets the wire size. These are the longest one-way runs that keep drop within the 3% recommended by the NEC 210.19(A) informational note, for 1/0 AWG copper carrying 150 A.

Maximum one-way run length for 1/0 AWG copper at 150 A by system voltage.
System Typical use Max run at 3% Drop at 100 ft
120 V standard receptacle and lighting circuits 122 ft 2.95 V
240 V ranges, dryers, EV chargers, feeders 244 ft 2.95 V
12 V DC automotive, marine, solar and battery runs 12 ft 2.95 V

Single-phase, one-way distance, copper at 20 °C. Aluminum reaches its limit at roughly 60% of these distances for the same size. The 3% figure is a recommendation in an informational note, not a code requirement.

1/0 AWG wire size — diameter, area and resistance

Diameter

0.3249 in · 8.251 mm

Cross-section

53.475 mm² · 105,535 cmil

Nearest metric size

50 mm² (rounds down)

Copper resistance

0.0983 Ω per 1000 ft @ 20 °C

Aluminum resistance

0.1641 Ω per 1000 ft

Area

105.535 kcmil

Diameter is computed from the ASTM B258 definition d = 0.005 × 92^((36 − n)/39), not read from a rounded table. Resistance uses the annealed-copper constant 10.371 Ω·cmil/ft at 20 °C.

What 1/0 AWG wire is used for

The 0 gauge mistake worth knowing

1/0 and 1 AWG are one step apart and sound almost identical when spoken. 1/0 is the LARGER conductor — 150 A vs 130 A copper at 75 °C. Ordering the wrong one is the most common aught-size mistake.