Illinois vs Indiana Electrical Code
Side-by-side comparison
| Factor | Illinois | Indiana |
|---|---|---|
| NEC edition | NEC 2008 | NEC 2017 |
| Compliance score | 47/100 (Permissive) | 72/100 (Moderate) |
| Electrician license | Required | Required |
| License name | Electrical License (varies by jurisdiction) | Electrical Contractor License |
| Permits required | Yes | Yes |
| State amendments | No | Yes |
| Homeowner exempt | Yes | Yes |
Key differences
- Indiana uses a more recent NEC edition (2017 vs 2008), meaning it has the latest safety requirements including expanded GFCI coverage and updated load calculation methods.
- Indiana has state-specific amendments to the NEC, indicating active code review and oversight.
Licensing requirements
Illinois
Illinois requires a Electrical License (varies by jurisdiction) through the Local jurisdictions (no statewide license). Homeowners are exempt for work on their own primary residence.
Indiana
Indiana requires a Electrical Contractor License through the Indiana Fire Prevention and Building Safety Commission. Homeowners are exempt for work on their own primary residence.
Wire sizing is identical. NEC Table 310.16 ampacity values have not changed since NEC 2017. Whether you are wiring in Illinois or Indiana, a 20A circuit uses 12 AWG copper and a 30A circuit uses 10 AWG copper. The differences between states are in code enforcement, not in the wire sizing itself.
GFCI requirement differences
Because Indiana uses NEC 2017 and Illinois uses NEC 2008, there are differences in GFCI coverage:
The GFCI differences between NEC 2017 and NEC 2008 are minor for most residential work. The most significant changes came in NEC 2023 with expanded kitchen and basement coverage. See our GFCI guides by room for details.
Frequently asked questions
Which state has stricter electrical codes, Illinois or Indiana?
Indiana has stricter enforcement with a score of 72/100 vs 47/100. The score reflects NEC edition recency, licensing requirements, permit enforcement, and state amendments.
Is my electrician license from Illinois valid in Indiana?
Electrician licenses are generally not transferable between states. If you hold a license in Illinois, you will typically need to apply separately in Indiana. Some states offer reciprocity agreements, but these vary. Contact the licensing authority in Indiana directly for requirements.
Is the wire size different in Illinois vs Indiana?
No. Wire sizing per NEC Table 310.16 is identical regardless of which NEC edition a state enforces. A 20A circuit requires 12 AWG copper in both Illinois and Indiana. The ampacity values have not changed since NEC 2017.
Do both Illinois and Indiana require electrical permits?
Both states require electrical permits for most work. Common permit-required projects in both states include new circuits, panel upgrades, service changes, and EV charger installations.
Does the NEC edition difference between Illinois and Indiana matter for my project?
For most residential work (circuits, outlets, fixtures), the NEC edition difference has minimal practical impact because wire sizing tables are unchanged. The biggest difference is GFCI coverage: NEC 2023 requires GFCI in all kitchen outlets and finished basements, while older editions are narrower. If you are doing a kitchen or basement remodel, the edition difference matters.
NEC 2023 references verified April 2026