150 amp wire size

150 Amp Wire Size

A common 150 amp feeder planning lookup is 1/0 AWG copper or 3/0 AWG aluminum, subject to code and equipment details.

Inputs

Results

Immediate estimate

Common 150 amp conductor1/0 AWG copperLimited feeder planning lookup; verify 75C/60C terminal path and installation conditions.

Circuit or service rating150 A

MaterialCopper

Run length75 ft

Voltage dropNot estimated

Acknowledge the limitations before relying on this as a planning lookup.

Electrical sizing depends on the adopted NEC edition, terminal temperature ratings, insulation type, conductor material, conduit fill, derating, grounding, equipment labels, and local inspection requirements.

Diagram

150 amp wire lookup

A 150 amp rating and conductor material select a limited planning row.

150 A rating
Material
Run length

How this calculator works

Select conductor material and run length for a cautious 150 amp planning lookup.

Lookup scope

The engine maps 150 amps to common copper and aluminum planning rows.

Length flag

One-way runs over 100 feet are flagged for voltage-drop review.

Electrical safety

The result is not a design approval and does not include all NEC adjustment factors.

Lookupmatch amp rating and conductor material to a common residential planning row

Length flagflag one-way runs over 100 ft for voltage-drop review

Assumptions

Lookup scope: Limited feeder planning lookup; verify 75C/60C terminal path and installation conditions.
Not checked: Voltage drop, grounding conductor size, neutral load, service load calculation, conduit fill, ambient temperature correction, bundling, and equipment-specific requirements.

Worked examples

150 amp copper feeder

Common copper planning lookup.

1/0 AWG copperCommon 150 amp conductor

Long aluminum run

Shows voltage-drop caution.

3/0 AWG aluminumCommon 150 amp conductor

FAQ

Is 150 amp service wire different from feeder wire?

It can be. Service and feeder rules are not always identical.

Does this work for underground cable?

Only as planning context. Underground wiring method and conductor type can change sizing.

Does conduit fill matter?

Yes. Conduit fill and derating can affect the final installation.

Sources and review

National Electrical Code, NFPA. Accessed 2026-07-16.
Calculators, Southwire. Accessed 2026-07-20.

Reviewed 2026-07-20. Planning estimates only; confirm project-specific requirements.