The Selective Service System is a United States government agency that maintains a database of potential conscripts for military service. All male U.S. citizens and male immigrants between the ages of 18 and 25 are required to register with the Selective Service System within 30 days of their 18th birthday.
There are several ways to apply for selective service. The most common way is to register online at the Selective Service System’s website. You can also register by mail or by phone. If you are unable to register online, you can request a paper registration form from the Selective Service System.