For best results, all forms mentioned below must be printed out, filled out and signed in ink, and mailed directly to OPM at the following address:
U.S. Office of Personnel Management
Attn: Federal Employee Retirement System
Post Office Box 45
Boyers, PA 16017-0045
In order to send directly to OPM, you must wait 30 days after your last day at GSA. However, because part of the process requires you to mail some forms to your financial institution and wait for them to send them back, you can start the process about 15 days after your last day.