What Size Wire for an EV Charger? NEC 625 Complete Guide 2026
The wire size for an EV charger depends on the charger amperage. A 48A charger (Tesla Wall Connector, ChargePoint Home Flex) needs 6 AWG copper wire with a 60A breaker. A 32A charger needs 8 AWG with a 40A breaker. The key NEC rule: EV chargers are continuous loads (NEC 625.41), so the breaker must be rated at 125% of the charger's maximum current.
NEC 625 — EV Charger as Continuous Load
NEC Article 625 classifies all EV charging equipment as a continuous load because it operates at maximum current for 3+ hours. Per NEC 625.41 (formerly 625.21), the branch circuit must be rated at 125% of the maximum current. For a 48A charger: 48A × 1.25 = 60A. For a 32A charger: 32A × 1.25 = 40A. This determines both the breaker size and the minimum wire gauge.
Wire Size Chart for Every EV Charger
16A charger (Level 1+): 12 AWG wire, 20A breaker — used with NEMA 6-20 outlet. Adds ~12 miles/hour. 24A charger: 10 AWG wire, 30A breaker. Adds ~18 miles/hour. 32A charger (most popular): 8 AWG wire, 40A breaker — used with NEMA 14-50 outlet at reduced power. Adds ~25 miles/hour. 40A charger: 8 AWG wire, 50A breaker. Adds ~30 miles/hour. 48A charger (maximum residential): 6 AWG wire, 60A breaker. Adds ~44 miles/hour. This is the fastest Level 2 charging available.
GFCI Protection per NEC 625.54
NEC 625.54 requires GFCI protection for all EV charging equipment, whether hardwired or cord-connected. This is typically accomplished with a GFCI breaker at the panel. Most modern EV chargers (Tesla Wall Connector, JuiceBox, ChargePoint) have built-in GFCI protection, which satisfies NEC 625.54 without needing a GFCI breaker. Check your charger specifications — if it has listed GFCI, a standard breaker is fine. If it does not, install a GFCI breaker.
NEMA 14-50 Outlet vs Hardwired
A NEMA 14-50 outlet with 50A breaker and 6 AWG wire is the most versatile option. It supports any plug-in charger up to 40A (32A continuous), and you can easily swap chargers or take it when you move. A hardwired installation on a 60A circuit supports the full 48A charging speed. Some chargers (like Tesla Wall Connector) work both ways but deliver maximum power only when hardwired to a 60A circuit. For future-proofing, install a 60A circuit with 6 AWG wire regardless — you can always use a smaller charger but cannot exceed the wire rating.
| Charger Amps | Wire Size (Cu) | Breaker | Outlet Type | Miles/Hour |
|---|---|---|---|---|
| 16A | 12 AWG | 20A | NEMA 6-20R | ~12 mi/hr |
| 24A | 10 AWG | 30A | NEMA 14-30R | ~18 mi/hr |
| 32A | 8 AWG | 40A | NEMA 14-50R | ~25 mi/hr |
| 40A | 8 AWG | 50A | NEMA 14-50R | ~30 mi/hr |
| 48A | 6 AWG | 60A | Hardwired | ~44 mi/hr |
Installation Cost and Considerations
Typical installation cost: $500-$1,500 depending on panel distance and existing capacity. The 30% federal tax credit (IRC §30C) covers up to $1,000 of charger + installation costs. Check panel capacity before installing — a 48A charger on a 60A circuit takes significant panel space. For 200A panels, this is usually fine. For 100A panels, consider a load management device or panel upgrade. Wire run: keep under 50 feet to minimize voltage drop. For longer runs, upsize to 4 AWG copper. Use our Voltage Drop Calculator.
Disclaimer: For educational reference only. Consult a licensed professional.