Every USCIS receipt number contains hidden information about your immigration case—the processing center, fiscal year, workday, and unique case identifier. Understanding these codes (LIN, SRC, EAC, WAC, IOE, and others) helps you track your application’s progress and know exactly where your case stands in the system.
📋 Receipt Number Structure Explained
Example Decoded
LIN2512350001 = Nebraska Service Center (LIN) + Fiscal Year 2025 (25) + Workday 123 + Case #50001. This tells you your case is at the Nebraska center, received in FY2025, and was the 50,001st case processed on workday 123.
USCIS Service Center Codes
The first three letters of your receipt number identify which USCIS facility is processing your case. Each service center has one or more letter codes assigned to it.
| Code | Service Center | Location | Common Case Types |
|---|---|---|---|
| LIN / NSC | Nebraska Service Center | Lincoln, NE | I-140, I-129 (H-1B), I-131, I-765 |
| SRC / TSC | Texas Service Center | Dallas, TX | I-140, I-129, I-130, asylum cases |
| EAC / VSC | Vermont Service Center | St. Albans, VT | I-140, I-129, I-539, religious workers |
| WAC / CSC | California Service Center | Laguna Niguel, CA | I-140, I-129, entertainment visas |
| MSC / NBC | National Benefits Center | Lee’s Summit, MO | I-485, I-130, naturalization support |
| YSC | Potomac Service Center | Arlington, VA | VAWA, T/U visas, special cases |
| IOE | Electronic / ELIS System | Online Processing | Cases filed online or converted to electronic |
IOE Receipts — Electronic Processing
Receipt numbers starting with IOE indicate cases processed through USCIS’s Electronic Immigration System (ELIS). This includes cases filed online and paper filings that have been electronically converted. IOE cases follow the same tracking process as traditional receipts.
Understanding the Numbers
📅 Fiscal Year (Digits 4-5)
🔢 Workday & Case Number (Digits 6-13)
Workday ≠ Calendar Day
The 3-digit “workday” indicates when USCIS processed your fee and generated the receipt—not when you mailed or when USCIS received your application. There may be a delay between mailing, lockbox intake, and fee processing.
Lockbox Facilities vs. Service Centers
When you mail an immigration application, it first goes to a USCIS lockbox facility—not directly to a service center. Understanding this two-step process helps set realistic expectations for processing times.
- First stop for mailed applications
- Operated by contractor (not USCIS staff)
- Check for correct forms and fees
- Scan documents into system
- Generate receipt number
- Forward to assigned service center
- Processing time: 2-4 weeks
- Adjudicate (approve/deny) applications
- Staffed by USCIS officers
- Review evidence and documentation
- Issue RFEs (Requests for Evidence)
- Make final decisions
- Issue approval/denial notices
- Processing time: varies by form
USCIS Lockbox Locations
USCIS operates lockbox facilities in Chicago, IL, Phoenix, AZ, Dallas, TX, and Lewisville, TX. The mailing address on USCIS forms directs you to the appropriate lockbox based on your form type and jurisdiction.
How to Use Your Receipt Number
✅ What You Can Do With Your Receipt Number
🔗 Useful USCIS Links
⏱️ When to Inquire
Frequently Asked Questions
Your receipt number appears on the I-797C Notice of Action (receipt notice) that USCIS mails after accepting your application. It’s in the upper left corner, labeled “Receipt Number.” If you filed online, you’ll also receive it via email and can find it in your USCIS online account.
IOE indicates your case was filed electronically or has been converted to electronic processing through USCIS’s ELIS (Electronic Immigration System). IOE receipts function the same as traditional center-based receipts for tracking purposes. The “E” stands for “Electronic.”
USCIS transitioned from older 3-letter codes to newer ones over time. For example, LIN (LINcoln) and NSC (Nebraska Service Center) both refer to the Nebraska center. Similarly, SRC and TSC both mean Texas. You may see either code depending on when your case was filed.
Yes, if your case was transferred between service centers. When USCIS transfers a case, they issue a new receipt number with the new center’s code. The fiscal year, workday, and case number portions may change. Track both receipt numbers, as some updates may reference the original.
Not precisely. The receipt number shows when USCIS processed your fee (workday), but your priority date depends on the form type. For I-140s, the priority date is usually when USCIS received the petition. For I-485s based on an approved I-140, the priority date carries over from the I-140.
For paper filings, expect 2-4 weeks for the lockbox to process your application and mail a receipt notice. For online filings, you typically receive confirmation immediately and a formal receipt within days. Check your USCIS online account for updates.
If you filed online, log into your USCIS online account to retrieve your receipt number. For paper filings, you can request a duplicate by calling the USCIS Contact Center at 1-800-375-5283 or submitting an e-Request through the USCIS website. You may also find the receipt number on subsequent notices (RFE, approval).
No. The receipt number only identifies the service center, fiscal year, processing date, and case sequence. It does not contain information about the assigned officer. Officer assignments are internal and not disclosed to applicants.
Disclaimer: This guide is for informational purposes only and does not constitute legal advice. USCIS procedures and processing times are subject to change. Always verify current information on the official USCIS website.
