How to search for sex offenders in Illinois
Two ways to check the Illinois sex offender registry: manually on the official state site, or programmatically across Illinois and every other US registry with a single API call.
Option 1 — Search the official Illinois registry
- Open the official Illinois sex offender registry public search.
- Search by last name (required), first name, or by city / ZIP / address.
- Open a result to see offenses, registration status, and known addresses.
- Note the record URL — it’s the authoritative source for that person.
The public Illinois site is best for a one-off, manual lookup. It won’t scale to bulk screening or cover other states in one search.
Option 2 — Search Illinois with the Offendersearch API
One authenticated request queries the Illinois registry plus the national NSOPW source, de-duplicates people across sources, scores each match, and returns provenance and freshness on every record.
POST /v1/search
{
"query": { "lastName": "Doe", "state": "IL" },
"jurisdictions": ["IL", "NSOPW"],
"locationScoped": true,
"freshness": "standard"
}This is a live demo of the API shape returning sample data. Real, scored results across every registry require a free account with billing enabled.
Illinois search FAQ
Is searching the Illinois sex offender registry free?
Searching the official Illinois public registry directly is free. The Offendersearch API is for teams that need programmatic, scored, multi-source results across Illinois and every other jurisdiction in one call.
Can I search sex offenders near an address in Illinois?
Yes. Provide a city, ZIP, or latitude/longitude with a radius and the API returns registrants near that location in Illinois, each scored and tagged with its source.
How current is Illinois registry data?
Every record returns a lastCheckedAt timestamp. Choose the Standard, Weekly, or Daily freshness tier depending on how recently Illinois data must have been re-verified.