Is your state's building code a decade out of date?
We checked which edition of the residential building code all 50 states currently enforce, verified against each state's own primary source.
The short answer
Every state builds on the same model code, but how recently each one updated it varies by almost a decade.
The International Residential Code (IRC) is republished every three years with updated safety, energy, and construction standards. States adopt it on their own timeline, and some move much faster than others. We pulled the current adopted edition for all 50 states directly from state building departments, legislative records, and code council filings, not secondhand summaries.
What we found
The spectrum
Here's where every state falls, from the newest active edition to the oldest, plus the 13 states with no statewide code to compare against. Every figure was checked against that state's own primary adoption source.
| State | Current edition | Effective date |
|---|---|---|
| New Jersey | 2024 IRC | Aug. 17, 2026 |
| North Dakota | 2024 IBC/IRC | Jan. 1, 2026 |
| Georgia | 2024 IRC | Jan. 1, 2026 |
| California | 2025 CRC (2024 IRC) | Jan. 1, 2026 |
| New York | 2025 Uniform Code (2024 IRC) | Dec. 31, 2025 |
| Iowa | 2024 IRC | Mandatory statewide |
| Connecticut | 2022 code (2021 IRC) | Current |
| Florida | 2021 IRC (8th Ed., 2023) | Current |
| Pennsylvania | 2021 UCC | Jan. 1, 2026 |
| Michigan | 2021 IRC | Aug. 29, 2025 |
| Maine | 2021 IRC (MUBEC) | Apr. 7, 2025 |
| Massachusetts | 2021 IRC (10th Ed.) | Fully eff. June 2025 |
| New Hampshire | 2021 IRC | July 2024 |
| Virginia | 2021 USBC | Jan. 18, 2024 |
| Washington | 2021 IRC | Mar. 15, 2024 |
| Maryland | 2021 IBC/IRC | May 29, 2023 |
| South Carolina | 2021 IRC | Jan. 2023 |
| New Mexico | 2021 IRC | July 2023 |
| Utah | 2021 IRC | July 2023 |
| Oregon | 2021 IRC | Oct. 2023 |
| Louisiana | 2021 IRC (LSUCC) | Current |
| Alabama | 2021 IRC | Current |
| Arkansas | 2021 (AFPC Vol. III) | Current |
| Delaware (New Castle, Sussex) | 2021 IRC | 2023–2024 |
| North Carolina | 2018 NCRC** | Current |
| Rhode Island | 2018 IRC | Feb. 2022 |
| Oklahoma | 2018 IRC, becomes 2024 IRC | Sept. 14, 2026 |
| Idaho | 2018 IRC | Current |
| Hawaii | 2018 IBC/IRC | Current |
| Montana | 2018 IRC | Current |
| Indiana | 2018 IRC | Current |
| Ohio | 2018 IRC | Current |
| Tennessee | 2018 IRC | Current |
| Minnesota | 2018 IRC | Current |
| Delaware (Kent) | 2018 IRC | Current |
| Kentucky | 2015 IRC | Current |
| West Virginia | 2015–2018 (opt-in) | Varies by county |
| Wisconsin | Own code (UDC), no ICC edition | Continuously updated |
| Wyoming | No mandatory code (2021 baseline, not required)* | N/A |
| Texas | No statewide code | N/A |
| Missouri | No statewide code | N/A |
| Illinois | No statewide code | N/A |
| Arizona | No statewide code | N/A |
| Colorado | No statewide code | N/A |
| Nevada | No statewide code | N/A |
| Kansas | No statewide code | N/A |
| Mississippi | No statewide code | N/A |
| Alaska | No statewide code | N/A |
| Vermont | No statewide code (single-family) | N/A |
| South Dakota | No statewide code | N/A |
| Nebraska | No statewide code | N/A |
*Wyoming's 2021 baseline binds only jurisdictions that choose to enforce a code. Adoption itself isn't mandatory. **North Carolina published a "2024" edition (based on 2021 IRC) with a July 2025 effective date; that date has since been postponed indefinitely, so the 2018 code remains active. Editions and dates change, so confirm with your state building department before relying on this table for an active project.
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Hover any state below for its exact edition, effective date, and any split or non-mandatory rule. You're welcome to embed it on your own site.
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Three stories behind the table
What's actually happening right now
- New Jersey just changed. The state adopted the 2024 International Codes on August 17, 2026, three weeks before this study's publish date. If you're permitting a New Jersey project and haven't rechecked the code recently, it may already be outdated.
- Oklahoma is mid-flip this week. The state moves from the 2018 to the 2024 IRC on September 14, 2026, three days after this study's publish date. Anyone permitting in Oklahoma right now is on the edge of two different code eras.
- North Carolina tried to update, and stalled. The state published a "2024" residential code (itself based on 2021 IRC) with a mandatory effective date of July 1, 2025. That date has since been postponed indefinitely. North Carolina is still building under its 2018 code today, the only state in this comparison that attempted a transition and had it stick mid-process.
How we did this & sources
This analysis is based on StateDataIndex's database of residential building-permit rules, which tracks requirements at the state and county level across the United States. For this study we verified the currently enforced residential code edition for all 50 states against each one's own primary source, a state legislative filing, a state building department's own adoption notice, or the official ICC state-adoption record, rather than relying on secondhand summaries.
Where a state's formal adoption date differs from the date it becomes mandatory for new permits (a common pattern when states allow a grace period for permits already in process), we used the date that applies to new permits filed today. Thirteen states have no mandatory statewide residential code; in those states, the applicable edition is set independently by each city or county, and can vary within the same state. This data reflects code adoption as of September 11, 2026. Because every state updates on its own cycle, confirm with your local building department before relying on any single figure here for an active project.
Questions or a correction? Email hello@statedataindex.com.
Use this data
Free to cite & republish
Journalists and writers are welcome to use these findings and the table, with a link back to the source. Suggested attribution:
Source: StateDataIndex, "Is Your State's Building Code Outdated? A 50-State Comparison (2026)", https://statedataindex.com/studies/building-code-age-by-state