310.12 Dwelling services and feeders
What changed in 310.12
The dwelling service and feeder sizing rule moved to 310.12, and the table is back: Table 310.12 for 120/240V single-phase dwellings from 100 to 400 amps.
Point by point
- The dwelling sizing rule moved from 310.15(B)(7) to its own section, 310.12, and the conductor table returned as Table 310.12.
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This section across NEC® editions
2020 NEC®RevisedYou're here
The dwelling service and feeder sizing rule moved to 310.12, and the table is back: Table 310.12 for 120/240V single-phase dwellings from 100 to 400 amps.
2023 NEC®No change
This section did not change from 2020 to 2023.
2026 NEC®Revised
The correction and adjustment sentence moved up to cover all dwelling service and feeder conductors, and Table 310.12(A) now needs 75°C or higher conductors.
Open the 2026 page →More 2020 changes in Article 310
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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