The AWG 2 amp rating depends entirely on the conductor material and the temperature rating of your equipment terminations. Per the 2023 and 2026 NEC Table 310.16, 2 AWG copper wire is rated for 115 amps (75°C column) and 2 AWG aluminum wire is rated for 90 amps (75°C column). These values assume an ambient temperature of 30°C (86°F) and no more than three current-carrying conductors in a raceway.

Below is the complete reference data, followed by the specific rules for selecting the correct temperature column, applying derating factors, and understanding the physical limits the table ignores.

The AWG 2 Amp Rating Reference Table (NEC Table 310.16)

This table provides the allowable ampacities for insulated conductors. Use the quick-jump links to find your specific wire size, or scroll through the adjacent sizes to compare voltage drop and conduit fill trade-offs.

How to read this table: The columns are split by conductor material (Copper vs. Aluminum/Copper-Clad) and then by temperature rating (60°C, 75°C, 90°C). The temperature rating represents the maximum heat the wire insulation can withstand before degrading. However, your final allowable ampacity is usually bottlenecked by the temperature rating of the terminations (lugs and breakers), not just the wire itself.

Source: NFPA 70 (NEC) Table 310.16. Ambient temperature 30°C (86°F). Not more than three current-carrying conductors.
AWG / kcmil Copper 60°C Copper 75°C Copper 90°C Aluminum 60°C Aluminum 75°C Aluminum 90°C
4 AWG 70A 85A 95A 55A 65A 75A
3 AWG 85A 100A 110A 65A 75A 85A
2 AWG (Target) 95A 115A 130A 75A 90A 100A
1 AWG 110A 130A 145A 85A 100A 115A
1/0 AWG 125A 150A 170A 100A 120A 135A
Jobsite Reality Check: A common myth is that 2 AWG aluminum is the standard for a 100-amp subpanel feeder. It is not. 2 AWG aluminum is rated for 90 amps in the 75°C column. If your calculated load is a full 100 amps, you must step up to 1/0 AWG aluminum (120A) or use 2 AWG copper (115A). You can only use 2 AWG aluminum on a 100A breaker if your actual calculated load is 90 amps or less.

Which Temperature Column Applies to Your Installation?

Beginners often look at the 90°C column because it offers the highest ampacity (130A for copper, 100A for aluminum). In practice, you are rarely allowed to use it for your final sizing. The rule governing this is NEC 110.14(C), which dictates that the ampacity of a circuit is limited by the lowest temperature rating of any connected component.

Here is how to select the correct column for your AWG 2 wire:

  • The 60°C Column (95A Cu / 75A Al): Use this for circuits rated 100 amps or less if the equipment does not have a marked temperature rating, or if you are using older NM-B (Romex) cable. While 2 AWG is almost never found in NM-B, if you are terminating 2 AWG THHN into an older, unmarked 1970s-era panelboard, the 60°C column applies by default.
  • The 75°C Column (115A Cu / 90A Al): This is the default for almost all modern residential and commercial installations. Modern breakers, panelboard lugs, and disconnect switches are tested and listed for 75°C terminations. If you are pulling 2 AWG THHN/THWN-2 in conduit to a modern 125A subpanel, your base ampacity is 115A (copper).
  • The 90°C Column (130A Cu / 100A Al): You can only use this column as your starting point for derating calculations (explained below). You cannot use the 90°C ampacity as your final allowable current unless both the wire and every single termination point in the circuit are explicitly rated and marked for 90°C, which is exceptionally rare in standard building wiring.

Derating AWG 2 Wire: When Base Ampacity Drops

The values in Table 310.16 assume ideal conditions: an ambient temperature of 30°C (86°F) and no more than three current-carrying conductors (CCCs) bundled together. When your installation deviates from these baselines, you must apply derating factors. This is where the 90°C column finally becomes useful.

According to NEC ampacity derating rules, you always start your derating math using the 90°C column, even if your terminations are only rated for 75°C. The final derated ampacity must then be compared to the 75°C column, and you must use the lower of the two numbers.

Scenario A: High Ambient Temperature

Imagine you are running 2 AWG copper THHN through an unconditioned attic in Arizona, where the ambient temperature reaches 113°F (45°C).

  1. Start with the 90°C copper ampacity: 130A.
  2. Apply the temperature correction factor for 41-45°C from Table 310.15(B)(1): 0.82.
  3. Calculate: 130A × 0.82 = 106.6A.
  4. Compare to the 75°C column limit (115A). Since 106.6A is lower, your new maximum allowable ampacity is 106 amps.

Scenario B: Bundling Conductors

If you pull two 240V circuits (4 hot wires) plus a shared neutral for a multi-wire branch circuit through the same conduit, you have 5 current-carrying conductors.

  1. Start with the 90°C copper ampacity: 130A.
  2. Apply the bundling adjustment factor for 4-6 CCCs from Table 310.15(C)(1): 80%.
  3. Calculate: 130A × 0.80 = 104A.
  4. Your final allowable ampacity drops to 104 amps. A 100A breaker is still acceptable, but you have lost the headroom to upsize the breaker to 125A.
Warning: If both high ambient temperature and bundling apply simultaneously, you must calculate both derating factors independently and apply the lowest resulting ampacity. Do not multiply the two factors together.

What the Ampacity Table Cannot Tell You

Table 310.16 only solves for thermal heating under continuous load. It completely ignores three critical physical and electrical realities that will cause an AWG 2 installation to fail inspection or perform poorly if overlooked.

1. Voltage Drop

The NEC ampacity tables do not account for distance. 2 AWG copper has a resistance of roughly 0.194 ohms per 1,000 feet. If you are feeding a detached garage 200 feet away with a 100-amp continuous load, the voltage drop will be approximately 7.7 volts (6.4% on a 120V circuit). While the NEC only recommends keeping voltage drop under 3% for branch circuits and 5% overall (Informational Note to NEC 310.15), sensitive electronics, EV chargers, and compressor motors will overheat or throw fault codes if the voltage sags below 114V under load. For runs over 100 feet at high amperage, you must calculate voltage drop and likely upsize to 1/0 or 2/0 AWG, regardless of what the thermal ampacity table permits.

2. Conduit Fill Capacity

2 AWG wire is thick and stiff. According to Southwire technical data and NEC Chapter 9 Table 5, a single 2 AWG THHN wire has a cross-sectional area of roughly 0.1158 square inches. If you are pulling a standard 4-wire feeder (two hots, one neutral, one ground) into a conduit, you are dealing with nearly 0.5 square inches of wire fill. NEC Chapter 9 Table 1 limits conduit fill to 40% for three or more wires. This means you cannot physically and legally pull four 2 AWG THHN wires into a 1-inch PVC Schedule 80 conduit; you must step up to at least 1.25-inch conduit to avoid jamming the wires and tearing the insulation during the pull.

3. Short-Circuit Withstand Rating

Ampacity measures how much current a wire can carry continuously without melting its insulation. It does not tell you how much fault current the wire can survive for the milliseconds it takes a breaker to trip. If a dead short occurs, thousands of amps flow instantly. If your utility transformer can deliver 40,000 amps of fault current, and your panel's busbars are only rated for 10,000 amps interrupting capacity (AIC), the 2 AWG wire might survive, but the panel will violently fail before the breaker clears the fault. Always verify the AIC rating of your panel and breakers matches your utility's available fault current, especially when installing heavy-gauge feeders close to the service entrance.