Quick answer: wire size for a 60 amp breaker
Minimum conductor whose table ampacity is at least 60 A, with not more than three current-carrying conductors at 30 °C (86 °F) ambient.
| Wire and terminal rating | Minimum size | Table ampacity |
|---|---|---|
| Copper, 60 °C column (NM cable, unmarked terminals) | 4 AWG | 70 A |
| Copper, 75 °C column (THHN/THWN-2, 75 °C terminals) | 6 AWG | 65 A |
| Aluminum, 60 °C column | 3 AWG | 65 A |
| Aluminum, 75 °C column (XHHW-2, SER, 75 °C terminals) | 4 AWG | 65 A |
NEC 110.14(C)(1)(a) limits circuits of 100 A or less to the 60 °C column unless the equipment is listed and marked for 75 °C, which most current breakers and panels are. The 90 °C column (75 A for 6 AWG copper) is only a starting point for derating.
6 AWG NM cable on a 60 amp breaker
6/3 or 6/2 NM-B is the most common question at this size. NM cable must use the 60 °C column (NEC 334.80), so 6 AWG copper NM-B is rated 55 A. Because 55 A is not a standard breaker size, NEC 240.4(B) allows the next size up, 60 A, when all three conditions hold:
- the conductors are not part of a branch circuit supplying more than one receptacle for cord-and-plug-connected portable loads,
- the conductor ampacity does not match a standard breaker rating, and
- the next higher standard rating is 800 A or less.
The calculated load still has to fit the 55 A conductor. A continuous load needs conductors rated at 125% of it (NEC 210.19(A)(1) and 215.2(A)(1)), so 6 AWG NM-B tops out at a continuous load of 44 A. For a full 60 A of conductor ampacity in NM cable, use 4 AWG (70 A).
Wire size for a 60 amp EV charger
| Charger output | Breaker (125%) | Copper THHN, 75 °C | Copper NM-B, 60 °C |
|---|---|---|---|
| 32 A | 40 A | 8 AWG (50 A) | 8 AWG (40 A) |
| 40 A | 50 A | 8 AWG (50 A) | 6 AWG (55 A) |
| 48 A | 60 A | 6 AWG (65 A) | 4 AWG (70 A) |
EV supply equipment is a continuous load, so NEC 625.41 sizes the breaker at 125% of the charger's rating and 210.19(A)(1) sizes the conductors the same way. A 48 A wall charger therefore needs a 60 A breaker and conductors rated at least 60 A. Most hardwired chargers need two hots and a ground, no neutral. Follow the charger's manual for the allowed conductor material and terminal temperature.
Wire size for 60 amps by distance (240 V)
Smallest size that keeps a 120/240 V single-phase run at or under a 3% voltage drop. The 48 A columns are for a continuous load on a 60 A breaker, such as an EV charger. Ampacity sets the floor, so the table never goes below 6 AWG copper or 4 AWG aluminum.
| Run | Cu, 60 A | Cu, 48 A | Al, 60 A | Al, 48 A |
|---|---|---|---|---|
| 50 ft | 6 AWG | 6 AWG | 4 AWG | 4 AWG |
| 75 ft | 6 AWG | 6 AWG | 4 AWG | 4 AWG |
| 100 ft | 6 AWG | 6 AWG | 4 AWG | 4 AWG |
| 125 ft | 4 AWG | 6 AWG | 3 AWG | 4 AWG |
| 150 ft | 4 AWG | 6 AWG | 2 AWG | 3 AWG |
| 200 ft | 3 AWG | 4 AWG | 1 AWG | 2 AWG |
| 250 ft | 2 AWG | 3 AWG | 1/0 AWG | 1 AWG |
| 300 ft | 2 AWG | 3 AWG | 2/0 AWG | 1/0 AWG |
Example: a 48 A EV charger in a detached garage 200 ft from the panel. 6 AWG copper reaches 152 ft at 48 A, so the run needs 4 AWG copper, which reaches 243 ft. The ground must then be upsized too (see ground).
Maximum length at 60 amps by wire size
The longest one-way run, in feet, before each size reaches the drop shown. Three-phase columns use the √3 formula. These are DC resistance figures.
Copper
| Size | 240 V, 3% | 240 V at 48 A, 3% | 240 V, 5% | 208 V 3-ph, 3% | 480 V 3-ph, 3% |
|---|---|---|---|---|---|
| 6 AWG | 122 | 152 | 203 | 122 | 282 |
| 4 AWG | 194 | 243 | 324 | 194 | 449 |
| 3 AWG | 244 | 306 | 408 | 245 | 565 |
| 2 AWG | 309 | 386 | 515 | 309 | 714 |
| 1 AWG | 389 | 487 | 649 | 389 | 899 |
| 1/0 AWG | 491 | 614 | 819 | 492 | 1135 |
| 2/0 AWG | 620 | 775 | 1034 | 620 | 1432 |
Aluminum
| Size | 240 V, 3% | 240 V at 48 A, 3% | 240 V, 5% | 208 V 3-ph, 3% | 480 V 3-ph, 3% |
|---|---|---|---|---|---|
| 4 AWG | 118 | 147 | 196 | 118 | 272 |
| 3 AWG | 148 | 186 | 248 | 148 | 343 |
| 2 AWG | 188 | 235 | 313 | 188 | 434 |
| 1 AWG | 237 | 296 | 395 | 237 | 547 |
| 1/0 AWG | 298 | 373 | 497 | 298 | 689 |
| 2/0 AWG | 377 | 471 | 628 | 377 | 871 |
| 3/0 AWG | 476 | 595 | 793 | 476 | 1099 |
| 4/0 AWG | 599 | 749 | 1000 | 600 | 1385 |
Formulas: single phase L = %·V·1000 / (2·I·R), three phase L = %·V·1000 / (√3·I·R), with R in ohms per 1000 ft. NEC 215.2(A)(1) Informational Note 2 recommends 3% on a feeder and 5% total. Use the voltage drop calculator for your exact load.
Ground wire for 60 amps
- Equipment grounding conductor: 10 AWG copper or 8 AWG aluminum, from NEC Table 250.122 for a 60 A breaker.
- Upsized hots: going from 6 AWG (26,240 cmil) to 4 AWG (41,740 cmil) is a ratio of 1.59, so under 250.122(B) the 10 AWG ground (10,380 cmil) must be at least 16,512 cmil, which is 6 AWG copper (26,240 cmil). 8 AWG copper is 16,510 cmil, just under the requirement, so the strict answer is 6 AWG copper.
Conduit size for 60 amp wire
Smallest conduit at 40% fill (NEC Chapter 9 Table 1) using THHN/THWN-2 areas from Chapter 9 Table 5.
| Run | Conductors | Area, in² | EMT | PVC 40 |
|---|---|---|---|---|
| Subpanel feeder, copper 75 °C (2 hots + neutral) | 3 × 6 AWG + 10 AWG | 0.173 | 3/4 | 3/4 |
| Subpanel feeder, aluminum 75 °C (2 hots + neutral) | 3 × 4 AWG + 8 AWG | 0.284 | 1 | 1 |
| 240 V EV charger or other 2-wire load, copper | 2 × 6 AWG + 10 AWG | 0.122 | 3/4 | 3/4 |
| Feeder upsized for 200 ft, copper | 3 × 4 AWG + 6 AWG | 0.298 | 1 | 1 |
XHHW-2 aluminum areas differ slightly from THHN, so check the conduit fill calculator for your insulation.
How much load can a 60 amp circuit carry?
| System | At 60 A | Continuous (48 A) |
|---|---|---|
| 120 V single phase | 7.2 kW | 5.8 kW |
| 240 V single phase | 14.4 kW | 11.5 kW |
| 208 V three phase | 21.6 kW | 17.3 kW |
| 480 V three phase | 49.9 kW | 39.9 kW |
| 600 V three phase | 62.4 kW | 49.9 kW |
Balanced load, unity power factor. The amps to watts calculator handles power factor.
When more than three wires share a conduit
With four to six current-carrying conductors in one raceway, NEC 310.15(C)(1) cuts ampacity to 80%. From the 90 °C column, 6 AWG copper drops to 60 A, which still covers 60 A as long as the 75 °C terminal rating (65 A) is also met. At seven to nine conductors (70%) it falls to 52 A, so upsize to 4 AWG (66 A). See wire derating.
In Canada
CEC Table 2 (copper) and Table 4 (aluminum) give the same ampacities for these sizes, so 6 AWG copper or 4 AWG aluminum carries 60 A at 75 °C. Rule 8-102 makes the 3% and 5% voltage drop limits mandatory, and distances are in metres. Use the Canadian wire size calculator or see CEC Table 2.
For larger circuits, see wire size for 100 amps and wire size for 200 amps.
This page is a quick reference. Confirm against the code edition your jurisdiction has adopted, the equipment markings and your inspector.