What Size Wire for a 20 Amp Circuit Breaker? (NEC Table 310.16)
Complete Copper vs. Aluminum AWG wire size, continuous load limit (16A max), ground wire gauge, and conduit sizing for 20A circuits (Kitchen, bathroom, garage, commercial 20A receptacles & small appliances).
Direct NEC Table 310.16 Answer for 20 Amps
Common Applications for a 20A Circuit
Kitchen, bathroom, garage, commercial 20A receptacles & small appliances. Remember that under the NEC 125% continuous-load rule (NEC 210.19 & 210.20), a standard 20A breaker can only supply up to 16A of continuous load (any load that runs for 3 hours or more without stopping, such as an EV charger or commercial lighting).
When to Upsize for Voltage Drop (Over 100 Feet)
If your one-way wire run exceeds 100 feet at 240V (or 50 feet at 120V), step up one wire gauge from 12 AWG to keep total line voltage drop under the NEC 3% branch-circuit recommendation. Use our Voltage Drop Calculator to check your exact footage.