What a receipt number is
A USCIS receipt number is usually made of three letters followed by ten digits. It appears on receipt notices and is used by USCIS systems to look up case status information.
Common prefixes include examples such as IOE, EAC, WAC, LIN, SRC, MSC, NBC, and others. The prefix can relate to how or where a filing is processed, but the exact case details should always be confirmed with USCIS.
Where people commonly find it
Many applicants find the receipt number on a USCIS notice, online USCIS account, or case communication. If you are unsure whether a number is correct, compare it carefully with the original notice before using it in an app.
CaseLuma uses receipt-number format checks to catch obvious entry mistakes before a lookup is attempted.
How CaseLuma helps
CaseLuma can keep receipt numbers, labels, review notes, and reminders easier to review on your device. Saved records are meant for organization, not for legal conclusions.
For live status checks, CaseLuma routes lookups through a secure backend so USCIS API credentials are not stored in the iPhone app.
FAQ
What format should a USCIS receipt number use?
Most receipt numbers use three letters followed by ten digits, such as IOE1234567890.
Is a receipt number the same as an Alien Registration Number?
No. A receipt number identifies a USCIS case or filing. An Alien Registration Number is a different identifier.
Does CaseLuma change my USCIS case?
No. CaseLuma is only an independent organization tool and status viewer. It does not file forms or change USCIS records.
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