Conduit Fill Calculator for New York, New York Electricians
New York (NEC 2020) electricians in New York use this free conduit fill calculator to verify that conductors fit within the 40% fill limit required by NEC Annex C for three or more conductors in a raceway.
Use the Calculator
Enter your conduit type, trade size, and conductor details for New York jobs below.
→ Open the Conduit Fill Calculator
Common New York Conduit Fill Scenarios
- 3/4″ EMT with 12 AWG THHN: NEC 2020 Annex C Table C1 allows up to 9 conductors at 40% fill. Common for New York residential and light commercial branch circuits.
- 1″ PVC Schedule 40 underground: New York underground feeders often use Schedule 40 PVC; check Table C11 of NEC 2020 Annex C for the correct fill limits.
- Mixed wire sizes: Use the calculator to sum cross-sectional areas and compare to the 40% limit when running mixed gauges in the same New York raceway.
Frequently Asked Questions
What is the conduit fill rule for New York, New York?
Under NEC 2020 (adopted in New York), the maximum fill for 3 or more conductors in any conduit is 40% of the conduit’s internal cross-sectional area (NEC Chapter 9, Table 1). New York contractors should verify any local amendments with the building department.
How many 12 AWG THHN wires fit in 3/4″ EMT for a New York job?
Per NEC 2020 Annex C Table C1, up to 9 conductors of 12 AWG THHN fit in 3/4″ EMT at 40% fill. Use the calculator to verify for your exact combination of conductor sizes and insulation types.