Electric Dryer Circuit: Complete Wiring Guide
Bill of materials
Electric dryers use a 30A/240V circuit with 10 AWG copper and NEMA 14-30R receptacle. NEC 2023 added GFCI protection for laundry areas, so new dryer circuits now require a GFCI breaker.
Standard electric dryers use a 30A 240V circuit with a NEMA 14-30R receptacle (4-prong). NEC 2023 requires GFCI protection for laundry circuits per 210.8(A)(10). Use 10/3 NM-B (Romex) for short runs or 10 AWG THHN in conduit.
30A dryer circuit (standard)
| Component | Specification | NEC basis |
|---|---|---|
| Wire (copper) | 10 AWG THHN | Table 310.16, 110.14(C) |
| Wire (aluminum alt.) | 8 AWG THHN | Table 310.16, 110.14(C) |
| Breaker | 30A double-pole | 240.4 |
| Voltage | 240V single-phase | |
| Conduit (EMT) | 1/2" EMT | Chapter 9 Table 4 |
| GFCI | Required (GFCI breaker or device) | 210.8(A)(10) |
| Max distance (3% VD) | 120 ft at 240V copper | 210.19(A) Note 4 |
Installation notes
This project requires GFCI protection per NEC 210.8(A)(10). The simplest approach is a GFCI breaker at the panel, which protects the entire circuit. For 240V circuits, use a 2-pole GFCI breaker sized to match the circuit. GFCI breakers cost $40-80 depending on amperage.
For the wire run, you have two options: NM-B cable (Romex) for interior runs through framing, or individual THHN conductors in conduit for exposed runs, outdoor installations, or runs through unfinished spaces. NM-B is faster to install but cannot be used outdoors or in conduit. For conduit, use EMT (metallic) or PVC Schedule 40.
Run length matters: every foot of wire adds voltage drop, reducing power to your equipment. The table below shows the exact voltage drop at common distances. If your run exceeds the 3% threshold, upsize one gauge.
Voltage drop by distance
Percentage voltage drop at common run lengths. NEC recommends 3% maximum for branch circuits and 5% for combined feeder plus branch.
| Distance | 10 AWG Co | 8 AWG Al | 8 AWG Co |
|---|---|---|---|
| 25 ft | 0.6% | 0.6% | 0.4% |
| 50 ft | 1.2% | 1.3% | 0.8% |
| 75 ft | 1.9% | 1.9% | 1.2% |
| 100 ft | 2.5% | 2.6% | 1.6% |
| 150 ft | 3.7% | 3.8% | 2.3% |
| 200 ft | 5.0% | 5.1% | 3.1% |
Common products for 10 AWG Copper circuits
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Related wire data
Detailed ampacity: 10 AWG copper, 8 AWG aluminum. Wire size lookup: 30A circuit. Calculators: voltage drop · panel load calculator.
Frequently asked questions
What wire size do I need for electric dryer circuit?
Use 10 AWG copper or 8 AWG aluminum on a 30A breaker at 240V. This is based on NEC 2023 Table 310.16 ampacity with 110.14(C) termination limits and 125% continuous load sizing per 210.19(A)(1).
Does electric dryer circuit require GFCI?
Yes. GFCI protection is required per NEC 210.8(A)(10).
NEC 2023 references verified April 2026