What Size Wire for Dishwasher? — Complete Wiring Guide
A Dishwasher requires 12 AWG copper (NEC 210.52(B)(2)) with a 20A on a 120V dedicated circuit. Here is the complete NEC-compliant wiring guide.
Dishwasher Wiring Details
Dishwashers draw 10-15 amps at 120V during the heating cycle. NEC requires a dedicated 20A circuit for a dishwasher — it cannot share with other appliances. Use 12/2 NM-B cable from a 20A breaker to a junction box under the counter. Many dishwashers are now cord-and-plug connected (with a power cord kit) rather than hardwired, which simplifies replacement. Either method is code-compliant.
NEC Code Reference
The wiring requirements for a Dishwasher are governed by NEC 210.52(B)(2). Always check the appliance nameplate for specific electrical requirements — the manufacturer's specifications take precedence over general guidelines. Your local AHJ (Authority Having Jurisdiction) may have additional requirements beyond the NEC.
Pro Tip
Some jurisdictions now require GFCI protection for dishwasher circuits per NEC 210.8(A)(7) — kitchens within 6 feet of a sink. Check your local amendments. If GFCI-protected, use a GFCI breaker rather than a GFCI outlet behind the dishwasher, since you cannot easily reach an outlet for reset.
Disclaimer: This guide is for reference only. All electrical work must be performed by or verified by a licensed electrician. Local codes may differ from NEC.