What Size Wire for a Dishwasher?
Wire and breaker sizing for a Dishwasher — the typical 120V 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.
On a 20A 120V circuit at 75°C terminations.
Protected by a 20A breaker (NEC 240.6).
GFCI required. The 2023 NEC (210.8(D) for specific appliances, 210.8(A) for kitchen/outdoor receptacles) requires GFCI protection here. Verify the code edition your jurisdiction has adopted.
Dishwasher Circuit Details
- A dishwasher uses a dedicated 120V circuit — 20A (12 AWG) is typical, 15A (14 AWG) is acceptable for smaller units.
- NEC 210.8(D) requires GFCI protection for dishwashers.
- Do not share the circuit with the disposal unless the appliance instructions allow it.
Long run to your dishwasher?
Over distance, voltage drop can require a larger wire than the table above. See the 20A wire size by distance:
Size it for your exact install
Open the calculator pre-filled with 20A at 120V to add distance, material and temperature.