Check USCIS immigration case status programmatically using the official Case Status API at developer.uscis.gov

Steps

1. Register for an API key at developer.uscis.gov and review the Case Status API documentation in the API Catalog.
2. Construct a GET request to the Case Status endpoint, supplying the 13-character receipt number (e.g., IOE-XXXX-XXXXX format) as a path or query parameter per the documented schema.
3. Parse the JSON response for the receiptNumber, formType, subType, receiptDate, and status fields; the status field contains a human-readable description of the current case stage.
4. Poll at a reasonable interval — the USCIS case processing pipeline updates asynchronously; daily polling is typically sufficient and avoids rate limit violations.
5. Map internal status descriptions to actionable states: 'Case Was Received', 'Request for Evidence Was Sent', 'Case Was Approved', 'Card Is Being Produced', 'Case Was Denied'.
6. Log receipt numbers and status snapshots with timestamps to detect transitions and trigger downstream notifications.