NEC Wire Sizing

What Size Wire for an Electric Wall Oven?

The breaker, copper and aluminum wire, and ground for a typical electric wall oven circuit, with the NEC basis and the nameplate caveats that actually decide it.

Quick answer: An electric wall oven typically needs a 40A / 240V circuit with #8 copper (or #8 aluminum) wire and a #10 copper ground.

Electric Wall Oven Circuit Spec

Typical branch circuit for an electric wall oven (nameplate rating)
Voltage240V
Breaker40A
Copper wire#8
Aluminum wire (75°C, SER or conduit)#8
Equipment ground (Cu)#10

Most single wall ovens (electric ovens) draw 20-30A and are placed on a 40A circuit, but always size to the nameplate. A double wall oven often needs a 50A circuit. Under the 2023 NEC (210.8(A)), a dwelling oven receptacle requires GFCI protection; this 2023 expansion is still being adopted, so verify your local edition. Wire sized at NEC Table 310.16 (copper lead at the 60°C column for NM-B); ground per NEC Table 250.122. The appliance nameplate lists the exact minimum circuit and maximum breaker; it always governs over a typical value.

Aluminum branch conductors are 75°C-rated AA-8000 alloy (SER cable, or XHHW-2 / THWN-2 in conduit); there is no 60°C aluminum NM-B, so the aluminum row uses the 75°C column. Where the terminations are rated 60°C only, size aluminum from the 60°C column instead (#6 here).

Adding this as a new load? Check whether your panel can handle it (the NEC 220.87 service check), or compare it against the breaker size by load chart.


Long Run? Size It Exactly

For a long run where voltage drop matters, or a nameplate that differs from the typical value, enter your exact load, distance, and conditions.

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Frequently Asked Questions

What size wire do I need for an electric wall oven?

An electric wall oven typically uses a 40A / 240V circuit, which calls for #8 copper (or #8 aluminum) conductors and a #10 copper equipment ground per NEC Table 250.122. Most single wall ovens (electric ovens) draw 20-30A and are placed on a 40A circuit, but always size to the nameplate. A double wall oven often needs a 50A circuit. Under the 2023 NEC (210.8(A)), a dwelling oven receptacle requires GFCI protection; this 2023 expansion is still being adopted, so verify your local edition.

What size breaker for an electric wall oven?

A 40A double-pole (240V) breaker. The #8 copper conductors are matched to that 40A rating. Do not oversize the breaker to a wire it does not protect: the breaker and the conductor go up together. Always confirm against the appliance nameplate, which lists the exact minimum circuit and maximum overcurrent device.

Can I use aluminum wire for an electric wall oven?

Yes. On the 75C column (the usual basis for aluminum), a 40A circuit needs #8 aluminum, versus #8 copper. Aluminum is common on larger circuits and services to save cost; apply antioxidant to the terminations, torque to the listed spec, and remember aluminum drops slightly more voltage on long runs.

What size breaker for an oven?

Same answer: oven is another name for an electric wall oven. It uses a 40A / 240V circuit with #8 copper wire and a #10 copper ground. Most single wall ovens (electric ovens) draw 20-30A and are placed on a 40A circuit, but always size to the nameplate. A double wall oven often needs a 50A circuit. Under the 2023 NEC (210.8(A)), a dwelling oven receptacle requires GFCI protection; this 2023 expansion is still being adopted, so verify your local edition.


Wire Size for Other Appliances