Massachusetts — Code Adoption Summary
Adoption model: Statewide-mandatory. Uses its own CMR chapter numbering rather than referring directly to IBC/NEC by name — must cross-reference for the underlying model-code edition.
Last verified: 2026-07-03
Confidence: verified
Primary sources: Mass.gov — 780 CMR (building) — https://www.mass.gov/massachusetts-state-building-code-780-cmr · 527 CMR (electrical/fire) · Building Energy Code — https://www.mass.gov/info-details/building-energy-code
Statewide adopted codes — 10th Edition, 780 CMR (mandatory since 2025-07-01)
| Code family | Adopted edition | Notes | Source |
|---|
| Building | 780 CMR 10th Ed. (2021 IBC base) | mandatory for permits ≥ 2025-07-01 (prior: 9th Ed./2015 IBC) | mass.gov |
| Electrical (NEC) | NEC 2023 (Massachusetts Electrical Code, eff. 2023-03-01) | separate from 780 CMR cycle | mass.gov |
| Fire | 527 CMR — NFPA 1, 2021 Ed. (eff. 2022-12-09) | | mass.gov |
| Energy | 780 CMR Ch. 11R (residential) / Ch. 13 (commercial) = IECC 2021 + MA amendments | base energy code | mass.gov |
| Stretch Energy Code (opt-in) | 225 CMR Ch. 22 (res.) / Ch. 23 (comm.) = IECC 2021 + stricter MA amendments | many cities/towns opt in — check locally | mass.gov |
| Plumbing | 248 CMR (Massachusetts Uniform State Plumbing Code — its own code, not straight IPC/UPC) | | mass.gov |
Adoption model & precedence
- 780 CMR/527 CMR/248 CMR apply statewide; individual municipalities may opt into the Stretch Energy Code (or the newer specialized/municipal opt-in code) — this is the main source of local variance.
- AHJ = local building/electrical inspector, applying the statewide base code plus whichever energy tier (base / stretch / specialized) the municipality has adopted.
Major cities / counties
| Jurisdiction | Notes | Building dept. |
|---|
| Boston | 780 CMR 10th Ed.; confirm Stretch/specialized code opt-in | boston.gov/isd |
| Cambridge | Frequently opts into Stretch/specialized energy code | cambridgema.gov |
| Worcester / Springfield | Base energy code common; confirm opt-in status | respective ISDs |
AHJ fallback (when local adoption is unverified)
- State baseline: 780 CMR 10th Ed. (2021 IBC), NEC 2023, base energy = IECC 2021 + MA amend.
- Action: confirm whether the municipality has opted into the Stretch or specialized (net-zero) energy code — this materially changes electrical/lighting/EV-readiness requirements.
Change log
- 2026-07-03 — created; verified 780 CMR 10th Ed. (mandatory 2025-07-01), NEC 2023, IECC 2021-based base + Stretch energy tiers.
