Is my TSP PIN the same as the PIN I use on other Government Web sites, such as Employee Express, PostalEase, myPay, etc.?
No. Your TSP PIN is not the same as a PIN assigned to you by your agency or any other Government agency or service. It is the 4-digit PIN that is assigned to you by the Thrift Savings Plan (or that you changed to a customized PIN) and can be used only for accessing your TSP account through the ThriftLine.