330.104 MC conductor sizes
What changed in 330.104
MC, NM, TC and UF cable can now hold smaller conductors, in step with Article 310 now allowing copper down to 16 AWG and copper-clad aluminum down to 14 AWG for 10-amp circuits.
Point by point
- The minimum conductor size allowed inside MC cable was lowered in the 2026 NEC®.
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- 3 more points on exactly what changed
- The 2023 rule next to the 2026 rule, side by side
- Why it changed
- What to do and check on the job
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This section across NEC® editions
2020 NEC®No change
This section did not change from 2017 to 2020.
2023 NEC®No change
This section did not change from 2020 to 2023.
2026 NEC®RevisedYou're here
MC, NM, TC and UF cable can now hold smaller conductors, in step with Article 310 now allowing copper down to 16 AWG and copper-clad aluminum down to 14 AWG for 10-amp circuits.
More 2026 changes in Article 330
This is a plain-English summary, not the NEC®'s exact wording. Always check the full section in the NEC® edition your area has adopted, plus any local amendments.
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