AHJ (Authority Having Jurisdiction)

An AHJ (Authority Having Jurisdiction) is the government body — almost always a city or county building department — that has legal authority to review, issue, and inspect building permits for a given property. The term comes from the building and fire codes (it appears throughout the International Building Code and NFPA standards) and refers to whoever enforces the adopted code in that place.

Why it matters for data: the AHJ is the original source of every permit record. When a contractor pulls a roofing or solar permit, it is the AHJ that records the application, assigns a permit number, and stamps the issue date. PermitStack ingests permits straight from each AHJ's open-data portal, so the permit you read in our API is the AHJ's own record — not a model estimate. One physical address has exactly one AHJ for building work, though a city and an overlapping county can each be an AHJ for different scopes (e.g. fire vs building).

See which AHJs we cover, and whether each is currently publishing, on the coverage page (522 active jurisdictions), and read how we ingest from them in our methodology.