25 Amp Breaker — Wire Size, Max Load & NEC Guide
A 25 Amp breaker requires 10 AWG copper wire. Max continuous load: 20A (80% rule). Max watts: 2,400W at 120V or 4,800W at 240V.
25 Amp Breaker — Complete NEC Guide
25A breakers are less common but used for specific equipment that exceeds 20A but does not require 30A. Often found with heat pumps and small central AC units.
The 80% Rule (NEC 210.20)
A 25 Amp breaker has a maximum continuous load of 20A (25A × 80%). Continuous loads are those expected to run for 3 hours or more. If your load exceeds 20A continuously, upsize to the next standard breaker size. Non-continuous loads can use the full 25A rating.
Wire Sizing (NEC 310.16)
Per NEC Table 310.16 at 75°C: a 25 Amp breaker requires 10 AWG copper conductor minimum. For aluminum, upsize two gauges. For runs exceeding 75 feet, use 8 AWG to keep voltage drop under 3%. Verify with our Wire Size Calculator and Voltage Drop Calculator.
Common Uses for 25 Amp Circuits
Small AC units, some water heaters.
Disclaimer: This guide is for reference. All electrical work must be verified by a licensed electrician. Local codes may differ from NEC.
Frequently Asked Questions
All Breaker Sizes — Wire & Load Reference
| Breaker | Wire | Max Cont. | Max W (240V) |
|---|---|---|---|
| 15 Amp | 14 AWG | 12A | 2,880W |
| 20 Amp | 12 AWG | 16A | 3,840W |
| 25 Amp | 10 AWG | 20A | 4,800W |
| 30 Amp | 10 AWG | 24A | 5,760W |
| 40 Amp | 8 AWG | 32A | 7,680W |
| 50 Amp | 6 AWG | 40A | 9,600W |
| 60 Amp | 6 AWG | 48A | 11,520W |
| 70 Amp | 4 AWG | 56A | 13,440W |
| 80 Amp | 3 AWG | 64A | 15,360W |
| 100 Amp | 1 AWG | 80A | 19,200W |
| 125 Amp | 1/0 AWG | 100A | 24,000W |
| 150 Amp | 2/0 AWG | 120A | 28,800W |
| 200 Amp | 3/0 AWG | 160A | 38,400W |
| 300 Amp | 350 MCM | 240A | 57,600W |
| 400 Amp | 500 MCM | 320A | 76,800W |