EnoughAmps

NEC 2023 vs. 2026: What Changed for Existing Homes

Updated · By Dariusz

The biggest change in the 2026 NEC® for homeowners is where and how existing-home load calculations work: they moved from Article 220 to Article 120, and the optional method for existing dwellings (now 120.83) treats new loads differently. Whether that helps or hurts you depends on what you're adding — and on your inspector.

What moved

Load calculation rules that lived in Article 220 for decades now sit in Article 120. For you, the section number changes from 220.83 to 120.83. The idea is the same: start from the loads you have and apply demand factors.

What changed in the method

Early analyses of the new text suggest the 2026 method no longer treats every new load the same way:1

  • New EV chargers and electric resistance heat reportedly count at a higher percentage.
  • Other new loads count at a lower percentage.

Interpretations are still settling, and inspectors apply the new rules differently. Treat any 2026 number — including ours, when we add it — as something to confirm locally.

Which edition should you use?

Use the edition your jurisdiction has adopted. States and cities adopt new editions on their own schedules, so a 2026 code book doesn't mean 2026 rules apply to your permit.2

Question Where to get the answer
Which edition applies? Your building department or electrician
How is a new EV charger counted? Your inspector, before you buy the charger
Does load management change the result? Your electrician — see panel upgrade vs. load management

Our free check defaults to NEC 2023, which is still the most widely adopted edition. Take your result and the questions in our Panel Capacity Worksheet to your electrician.

Technical notes

  1. NFPA offers free online read access to NFPA 70, so you or your electrician can read Article 120 directly instead of relying on summaries. Source: NFPA 70 (NEC®), free access. ↩

  2. NFPA publishes maps of the NEC® edition enforced in each state; many states keep an older edition for years after a new one is published. Source: NFPA NEC enforcement maps. ↩

Free download

Panel Capacity Worksheet

A printable sheet to map your panel, list your big appliances and ask an electrician the 10 questions that matter before a quote.

Questions

Which NEC edition applies to my home?

The one your state or city has adopted, which can lag the newest edition by years. Your local building department or electrician can tell you which edition your permit will be reviewed under.

Will NEC 2026 make my result better or worse?

It depends on what you're adding. Early readings suggest new EV chargers and resistance heat count more heavily than other new loads, so results can move either way. Ask your inspector how they apply it.

Why does EnoughAmps default to NEC 2023?

Most jurisdictions were still on 2023 or older when we launched, and inspectors' interpretations of the 2026 changes were still settling.

Sources