Green Card Number is located on the bottom of the back of the card, directly in the first line of this long set of characters. As we mentioned above, you should search for 13 digits starting with 3 letters. Those letters have their specific meaning, they stand for the U.S. Citizenship and Immigration service center that received your resident status case. On this specimen, you can see “LIN”.
LIN stands for Lincoln Service Center (now known as Nebraska Service Center). It means that your case was received there.
Right after the service center code, you can see two digits that represent the fiscal year the case was received. It is important to remember that the fiscal year is not the same as a calendar year. The fiscal year is counted from October 1 to September 30. To give you some perspective, as an example, if your case was received by a service center on the 15th of October, 2019, your Green Card Number would have a fiscal year of two numbers – 20. If a case was filed between October 2016 and September 2017, your Permanent Resident Card Number will have number 17 in this respective position.
Following the fiscal year, 3 digits indicate the workday that the case was opened on a computer. Those 3 numbers for workday are based on 365/366 days per year, minus holidays and weekends. So if your green card reads TSC 21 043, your case was received at the Texas Service Center in the 2021 fiscal year, on the 43rd workday.
The last 5 numbers represent your unique immigrant case number — the number of the approved case that finished in a success of a green card being granted to you.