An i551 number can also be referred to as a case number, receipt number, Green Card number, permanent resident card number, or permanent resident document number.
It is a 13 character long combination of letters and numbers; with three letters at the beginning followed by 10 numbers. It is different from your alien registration number and your USCIS number.
Where is the i-551 number located?
The number is printed on the back of a Green Card.
In this image “LIN0000000319” is the i-551 number.
Some older Green Cards might have the i-551 number located on the front of the card.
Use of i-551 number
It refers to your specific immigration case. The code is made up of numbers and letters that tell you specific things about your case.
- The first three letters refer to the services centers that received your case.
CSC – California Service Center
EAC – Eastern Adjudication Center (now known as Vermont Service Center)
IOE – ELIS (electronic filing)
LIN – Lincoln Service Center (now known as Nebraska Service Center)
MSC – Missouri Service Center (now known as National Benefits Center)
NBC – National Benefits Center
NSC – Nebraska Service Center
SRC – Southern Regional Center (now known as Texas Service Center)
TSC – Texas Service Center
VSC – Vermont Service Center
WAC – Western Adjudication Center (now known as California Service Center)
YSC – Potomac Service Center
- The next two digits refer to the fiscal year.
The fiscal year begins on October 1st and ends on September 30th. This is different from the calendar year, which starts on January 1st and ends December 31st.
- The next three digits refer to the computer workday
This is the same thing as a regular workday; it excludes weekends and holidays. For example, the fourth computer workday is the fourth workday of the fiscal year, or October 5.
- The last five digits refer to your case number.
