USCIS API Event Codes Decoder
Found a cryptic 3-letter or 4-letter status code (like IAF, IKA, or DA) in your myUSCIS raw case JSON? Use our interactive decoder tool below to translate any of the 500+ codes we know into plain English.
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USCIS processes all electronic cases (usually those starting with the IOE prefix) using the DHS Electronic Immigration System (ELIS). In the raw backend database, actions are tracked using shorthand database keys.
When you check the internal API status feed, you will see a list of actions labeled with codes such as eventCode: "IAF". These codes are defined by the federal government's National Information Exchange Model (NIEM).
Looking up one code at a time shows only part of the picture. Paste your case data on our home page to see every event in order, with silent updates marked and each code explained in plain English, including what it means for your case's timeline.
Commonly Checked CodesShowing 7 popular codes
| Code | Meaning |
|---|---|
| DA | DA APPROVED/NOTICE ORDERED |
| EA | EA DENIAL NOTICE ORDERED |
| FNB | FNB FINGERPRINTS TAKEN |
| FYD | FYD LEGALIZATION PHASE 1 L.O. RECOMMENDATION OF DENIAL |
| HA | HA RESPONSE TO REQUEST NOTICE TO APPLICATION/PETITION RECEIVED |
| IAF | IAF RECEIPT LETTER EMAILED |
| IKA | IKA INITIAL EVIDENCE REQUEST NOTICE SENT |
Understanding common code types
While our code table has 500+ event codes, most applicants will only encounter a few specific families of codes:
- Intake: the case arriving, such as
AALB(received at the lockbox) orIAF(receipt letter emailed). - Biometrics and checks:
IMAG(biometrics appointment scheduled),FNB(fingerprints taken) andFTA0(database check results received). - Requests for evidence (RFEs):
IK(request for additional evidence sent), thenHAorHAA(your response received). - Decisions:
DA(approved, notice ordered) orEA(denial notice ordered).
Why does the API use these codes?
These codes keep database sizes small and allow different Department of Homeland Security (DHS) databases to communicate with each other instantly. Because different agencies (USCIS, Customs and Border Protection, and Immigration and Customs Enforcement) all use different software interfaces, they rely on standardized NIEM codes as a universal translator.
By checking your raw JSON timeline events, you can spot these codes the moment an officer updates your database record. Sometimes this happens hours or even days before the main visual website updates its generic user messages. For an automated translation and analysis of all your timeline codes, try our main USCIS API case status tool.
See your own case, explained.
See every step USCIS has recorded for your case, in plain English: your timeline, silent updates, and what usually comes next for cases like yours.
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