1. Short title This Act may be cited as the TSP Modernization Act of 2017 . 2. Thrift Savings Plan account withdrawal flexibility (a) Post-Separation partial withdrawals Section 8433(c) of title 5, United States Code, is amended— (1) in paragraph (1)— (A) by striking and who has not made a withdrawal under subsection (h)(1)(A) may make one withdrawal and inserting may make one or more withdrawals ; and (B) by striking as a single payment and inserting in the same manner as a single payment is made ; and (2) by adding at the end the following: (5) Withdrawals under this subsection shall be subject to such other limitations or conditions as the Executive Director may prescribe by regulation. . (b) Limitation on return of payment relating to a change in election Section 8433(d) of title 5, United States Code, is amended— (1) in paragraph (1), by inserting , except that in the case of an election to receive an annuity, a former employee or Member may not change an election under this section on or after the date on which an annuity contract is purchased to provide for the annuity elected by the former employee or Member after this subchapter ; and (2) in paragraph (2)— (A) by striking change an and inserting return a payment that was made pursuant to an ; and (B) by striking on or after and all that follows through the former employee or Member . (c) Elimination of automatic annuity in absence of election Section 8433(f) of title 5, United States Code, is amended— (1) by striking (1) Notwithstanding and inserting Notwithstanding ; (2) by striking this paragraph and inserting this subsection ; and (3) by striking paragraph (2). (d) Allowance of multiple age-Based in-Service withdrawals Section 8433(h) of title 5, United States Code, is amended— (1) by striking paragraph (2); (2) by redesignating paragraphs (3), (4), and (5) as paragraphs (2), (3), and (4), respectively