Three columns, three answers
NM-B cable is held to the 60 °C column, THHN in conduit on 60/75 °C breakers uses 75 °C. That is why 4 AWG NM-B and 6 AWG THHN can both serve 60 A.
What size wire for 60 amps?
A 60 A circuit takes 4 AWG NM-B in the wall or 6 AWG copper THHN in conduit (75 °C), with a 10 AWG ground; aluminum needs 4 AWG. At an 48 A load the copper reaches 152 ft at 240 V (3 % drop). Used for 48 A EV chargers, small subpanels and tankless heaters.
02 · Ampacity · NEC 2023 Table 310.16
6 AWG copper · 90 °C insulation, 75 °C terminals, 30 °C, 3 conductors
USE:
6 AWG COPPER · 65 A ALLOWABLE · 60 A MAX BREAKER
Allowable
65 A
6 AWG Cu
Max breaker
60 A
ampacity ≥ breaker
For your load
6 AWG
60 A
6 AWG copper carries 75 A after derating from the 90 °C column and 65 A at its 75 °C terminals, so it is good for 65 A on a breaker up to 60 A.
- Meets NEC 2023 Table 310.16 at 75°C — verify with your local AHJ/inspector110.14(C)
- Load 60 A ≤ 65 A310.14
Derating math
- Table 310.16 at 90 °C
- 75 Aderating starts at the insulation rating
- Ambient factor
- × 1.0030 °C, Table 310.15(B)(1)
- Bundling factor
- × 1.003 current-carrying conductors, 310.15(C)(1)
- Derated
- 75 A
- Terminal limit (75 °C)
- 65 A110.14(C)
- Allowable
- 65 Athe terminals decide
6 AWG
- Copper 60 / 75 / 90 °C
- 55 / 65 / 75 ANM-B uses the 60 °C column (334.80)
- Aluminum 60 / 75 / 90 °C
- 40 / 50 / 55 A
- Largest breaker (Cu, 75 °C)
- 60 Aampacity ≥ breaker
- Solid diameter
- 0.162"4.12 mm · ASTM B258 formula
- Stranded (7 strands)
- 0.184"4.67 mm · Table 8
- THHN outside
- 0.254"6.45 mm · 0.0507 in² · Table 5
- Area
- 26,240 cmil13.30 mm² · nearest IEC 16 mm²
- DC resistance, 75 °C
- 0.491 Ω/1000 ftaluminum 0.808 Ω/1000 ft · Table 8
- Copper weight
- 79.4 lb/1000 ft
60 A circuit at a glance
Wire
- Copper NM-B (60 °C)
- 4 AWG
- Copper THHN (75 °C)
- 6 AWG
- Aluminum (75 °C)
- 4 AWG
Ground & breaker
- Copper ground
- 10 AWG
- Aluminum ground
- 8 AWG
- Continuous load max
- 48 A
- Breaker
- 60 A
Distance (3 %)
- Cu at 120 V, 48 A
- 76 ft
- Cu at 240 V, 48 A
- 152 ft
- Al at 240 V, 48 A
- 147 ft
60 A circuit tables 10 rows
Sort any column, print a shop sheet, download CSV. Click a row to load it in the calculator.
| Actions | |||||
|---|---|---|---|---|---|
| 4 AWG | 6 AWG | 10 AWG | 243 ft | ||
| 6 AWG | 6 AWG | 10 AWG | 152 ft | ||
| 4 AWG | 4 AWG | 8 AWG | 147 ft |
Feet one way (the current goes out and back). Ampacity is a separate check: a long run may need a heavier wire for drop, never a lighter one for heat.
05 / Field guide
60 amps:
which wire, which method.
A 60 A circuit takes 4 AWG NM-B in the wall or 6 AWG copper THHN in conduit (75 °C), with a 10 AWG ground; aluminum needs 4 AWG. At an 48 A load the copper reaches 152 ft at 240 V (3 % drop). Used for 48 A EV chargers, small subpanels and tankless heaters.
Breaker rules
240.4(B) lets a conductor whose ampacity is not a standard size take the next breaker up (not on multi-outlet receptacle circuits). The headline here uses ampacity at least 60 A.
Distance
The answer above is the minimum for heat. On a long run upsize for voltage drop, and grow the ground with it: the table below gives the longest 240 V run at 3 % for each candidate size.
Questions
Answered plainly.
01What size wire for a 60 amp breaker?
+−
4 AWG copper NM-B in the wall, 6 AWG copper THHN in conduit or 4 AWG aluminum, all with ampacity at least 60 A (NEC 2023 Table 310.16).
02Can I use 6 AWG wire on a 60 amp breaker in NM-B cable?
+−
Not at the ampacity rule: NM-B is limited to the 60 °C column (334.80), where 6 AWG carries 55 A; 240.4(B) next size up allows it on a single-load circuit.
03What size ground wire for 60 amps?
+−
10 AWG copper or 8 AWG aluminum (Table 250.122), larger in proportion if the circuit wire is upsized for distance (250.122(B)).
04How far can I run a 60 amp circuit?
+−
At 48 A (80 %) on 6 AWG copper, 152 ft one way at 240 V or 76 ft at 120 V before the drop passes 3 %. Beyond that, go up a size.
05What is the largest continuous load on a 60 amp circuit?
+−
48 A: a continuous load (3 hours or more) may use only 80 % of the breaker rating (the 125 % rule).
06Is 60 A the right circuit for a 48 A EV charger?
+−
Yes: 48 A × 125 % = 60 A. Use 6 AWG THHN in conduit or 4 AWG NM-B; 6 AWG NM-B (55 A) is not enough.