What Size Wire for Hot Tub / Spa? — Complete Wiring Guide
A Hot Tub / Spa requires 6 AWG copper with a 50A GFCI double-pole on a 240V dedicated with GFCI disconnect circuit. Here is the complete NEC-compliant wiring guide.
Hot Tub / Spa Wiring Details
Hot tubs and spas typically draw 20-50 amps at 240V depending on size and heater wattage. A standard residential hot tub with a 4-6 kW heater needs a 50A circuit with 6 AWG copper wire. NEC 680.42 requires a GFCI-protected disconnect within sight of and at least 5 feet from the spa. Many electricians install a 50A GFCI breaker in the main panel plus a non-fused disconnect at the hot tub location, or use a GFCI spa disconnect panel. The circuit must be a dedicated circuit — no other loads.
NEC Code Reference
The wiring requirements for a Hot Tub / Spa are governed by NEC Article 680.42. 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
Hot tub wiring has unique requirements. NEC 680.42 requires the disconnect to be at least 5 feet from the inside wall of the spa AND must be within line of sight. If the panel is not visible from the hot tub location, you need both a disconnect at the panel location and a local disconnect near the spa.
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.