What Size Wire for a Detached Garage?
Wire and breaker sizing for a Detached Garage — the typical 240V circuit, plus the code details (NEC 310.16) that change the answer.
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
6 AWG
On a 60A 240V circuit at 75°C terminations. 60°C terminations: 4.
Aluminum
4
Protected by a 60A breaker (NEC 240.6).
Voltage
240V
Breaker
60A
Connection
Hardwired
GFCI
Not required
Detached Garage Circuit Details
- A 60A feeder (6 AWG copper) is a common, flexible size for a detached garage sub-panel.
- Detached buildings need a disconnect and their own grounding electrode (ground rod) per NEC 225/250.
- Run 4 wires — two hots, neutral, ground — to a sub-panel with separated bars.
Long run to your detached garage?
Over distance, voltage drop can require a larger wire than the table above. See the 60A wire size by distance:
Size it for your exact install
Open the calculator pre-filled with 60A at 240V to add distance, material and temperature.