Yes, you can leave your entire account balance in the TSP when you leave federal service if the balance is $200 or more. You can continue to enjoy tax-deferred earnings and low administrative expenses. Once you separate, you will no longer be able to make employee contributions. However, you can transfer money into your TSP account from IRAs (although not from Roth IRAs) and eligible employer plans. Your account will continue to accrue earnings, and you can continue to change the way your money is invested in the TSP investment funds by making interfund transfers.