WireWicket / NEC lookup

Derived answer · NFPA 70 (NEC) 2026

How many 12 AWG THHN/THWN-2 conductors fit in 3/4-inch EMT?

For repeated 12 AWG THHN/THWN-2 conductors in 3/4-inch EMT, the supported NEC 2026 calculation gives a maximum of 16 conductors.

Static answer

16 conductors

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Assumptions

  • All conductors are identical 12 AWG THHN/THWN-2 conductors using the supported Table 5 area of 0.0133 in².
  • The raceway is EMT at the listed trade size, using its internal area from the supported Table 4 data.
  • The count includes only the identical conductors in the query; separately sized grounding, neutral, or other conductors are not added.
  • The count is evaluated under Chapter 9 Table 1 fill limits; conductor arrangement, installation conditions, and local amendments are outside this lookup.

Method

Chapter 9 Table 5 gives 0.0133 in² per conductor. For three or more conductors, Table 1 permits 40% of the 3/4-inch EMT area (0.5330 in²), or 0.2132 in². At 16 conductors, the total is 0.2128 in²; the next count (17) would use 0.2261 in² and exceed the permitted area.

Edition and source

NFPA 70 (NEC) 2026. Chapter 9, Table 1 (permitted fill); Table 4 (EMT raceway area); Table 5 (THHN / THWN-2 conductor area). Article 358 (EMT). View NFPA 70 (2026) in NFPA LiNK

Verify the edition adopted by your jurisdiction and any local amendments. This reference tool does not replace project review or AHJ requirements.

This page provides one derived calculation only; it does not reproduce the source tables.

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Raceway-fill maximum calculator

Choose supported conductor and raceway values to find the highest count that passes the same NEC fill calculation used by WireWicket’s raceway calculator.

Calculated maximum

16 conductors

Conductor area each
0.0133 in²
Total conductor area
0.2128 in²
Allowable area
0.2132 in² (40%)
Actual raceway fill
39.92%

The next count, 17, uses 0.2261 in² and exceeds its 0.2132 in² permitted area.

NFPA 70 (NEC) 2026; Chapter 9, Table 1 (permitted fill); Table 4 (EMT raceway area); Table 5 (THHN / THWN-2 conductor area). Article 358 (EMT). View NFPA 70 (2026) in NFPA LiNK

Verify the edition adopted by your jurisdiction and any local amendments. This reference tool does not replace project review or AHJ requirements.

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