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U.S. visa petitions are filed at the United States Citizenship and Immigration Services, under the Department of Homeland Security. Each case is assigned a unique identifying number known as a USCIS case number or receipt number. It is important to know your case number. You will need it to follow up your visa petition with the USCIS. To check your status online at the USCIS website, or by phone, you will need this receipt number.
1. Check your postal mail for an official letter from the USCIS. You should get one about a week after you submit your paperwork to them, though it could take longer. Look for your case receipt number on the first page. Your case number should be 13 digits long, made up of alphanumeric characters with dashes in between them.
2. Write down your case number. Notice that it is made up of four series of numbers or letters, divided by the minus signs or dashes These are four parts that tell you something about your USCIS case and the time it was received.
3. Read the first three figures starting from the left. These are 3 letters indicating the USCIS service center that your case went to. Where your visa application is forwarded to usually depends on what US state you live in.
EAC - Vermont Service Center
SRC - Texas Service Center
WAC - California Service Center
LIN - Nebraska Service Center
MSC - Missouri Service Center
4. Read the second series of figures. Interpet this as the fiscal year that the USCIS assigned you a case number. The fiscal year is different from the calendar year. It begins on October 1 and ends on September 30. So if your USCIS case was opened on October 2, 2008, it should have "09" on the case receipt number, as it falls within the fiscal year of 2009. Government agencies always use the fiscal year, so don't be confused.
5. Look at the third series of figures in your USCIS case number. Read this as the working day of the year that your case was opened. Or specifically, when the fee was processed. A figure of "001" usually means October 1, the first day of the fiscal year.
6. Read the fourth series of figures in your USCIS receipt number. These 5 digits represent the actual identification number assigned to your case.
7. Verify your USCIS case number by checking your case status. Go to uscis.gov to check your case status. You can also call the USCIS and follow the voice prompts. This will let you ensure you have a valid case number.